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Life Lexicon update -- NEW CALL FOR PROOFREADERS

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Life Lexicon update -- NEW CALL FOR PROOFREADERS

Postby dvgrn » December 27th, 2015, 11:23 pm

The tenth anniversary of the final update of Stephen Silver's Life Lexicon is coming up in two months. Since 2011 I've had a copy in my email archives of an unfinished 2007 draft of the Lexicon:

lecicon.diff:
2c2
<   Release 25, 2006 February 28
---
>   Release 26, 2007 April ? (unfinished)
39c39
<   This lexicon is copyright (C) Stephen Silver, 1997-2005.  It may be
---
>   This lexicon is copyright (C) Stephen Silver, 1997-2006.  It may be
161a162,185
> :17c/45 spaceship:  A {spaceship} travelling at seventeen forty-fifths
>    of the {speed of light}.  This is the strangest spaceship speed for
>    which there is any known example.  See {Caterpillar} for details.
>
> :2c/5 spaceship:  A {spaceship} travelling at two fifths of the
>    {speed of light}.  The only such spaceships that are currently known
>    travel orthogonally.  The first was found by Dean Hickerson in July
>    1991, and is shown below.
>    ...***...***...
>    ...*.*...*.*...
>    .*...*...*...*.
>    .*..*.....*..*.
>    .**.**...**.**.
>    ...***...***...
>    .....**.**.....
>    **..***.***..**
>    .*..***.***..*.
>    .*..**...**..*.
>
> :2c/7 spaceship:  A {spaceship} travelling at two sevenths of the
>    {speed of light}.  The only such spaceships that are currently known
>    travel orthogonally.  The first to be found was the {weekender},
>    found by David Eppstein in January 2000.
>
437c461
<    Holzwart in September 2004.
---
>    Holzwart in April 2004.
1040a1065,1066
> :bobsled:  See {switch engine channel}.
>
1252a1279,1362
> :c/12 spaceship:  A {spaceship} travelling at one twelfth of the
>    {speed of light}.  The only such spaceships that are currently
>    known are the {Cordership}s.
>
> :c/2 spaceship:  A {spaceship} travelling at half the {speed of light}.
>    Such spaceships necessarily move orthogonally.  The first to be
>    discovered was the {LWSS}.  For other examples see {Coe ship},
>    {ecologist}, {flotilla}, {hammerhead}, {hivenudger}, {HWSS},
>    {MWSS}, {puffer train}, {puff suppressor}, {pushalong},
>    {Schick engine}, {sidecar}, {still life tagalong} and {x66}.
>
> :c/3 spaceship:  A {spaceship} travelling at one third of the
>    {speed of light}.   All known c/3 spaceships travel orthogonally,
>    and the first was found in August 1989 by Dean Hickerson.  For
>    further examples see {brain}, {dart}, {edge-repair spaceship}, {fly},
>    {turtle} and {wasp}.  A spaceship moving diagonally at an angle of
>    45 degree cannot travel at a speed of c/3, but it is likely that c/3
>    {knightship}s exist, though none have yet been found.
>
> :c/4 spaceship:  A {spaceship} travelling at one quarter of the
>    {speed of light}.  The first such spaceship to be discovered was,
>    of course, the {glider}, and this remained the only known example
>    until December 1989, when Dean Hickerson found the first orthogonal
>    example and also a new diagonal example (the {big glider}).
>    For other examples see {B29}, {Canada goose}, {crane}, {Enterprise},
>    {edge-repair spaceship}, {non-monotonic}, {Orion}, {quarter},
>    {sparky}, {swan} and {tagalong}.  It is known that c/4 is the fastest
>    possible speed for a (45-degree) diagonal spaceship.
>
> :c/5 spaceship:  A {spaceship} travelling at one fifth of the
>    {speed of light}.  The first such spaceship to be discovered was the
>    {snail}, found by Tim Coe in January 1996.  The first diagonally
>    moving example was found by Jason Summers in November 2000.  In
>    January 2005, Summers found the smaller diagonal specimen shown
>    below.
>    ..........**..........
>    .........*..*.........
>    ........**............
>    .........*.**.........
>    ..........*.***.......
>    ..........**.***......
>    ............*....**...
>    ............***....**.
>    ..*.........*.*.......
>    .***........*..*......
>    *...**................
>    *..*.*.......**.*..*..
>    .*.**.****...*...****.
>    ....**.*...**.......*.
>    ....**.**..*.........*
>    .....*...*........*.**
>    ...........*.......*..
>    ......*.....*......*..
>    ......*.....*..*......
>    .......*...**...**....
>    .......*....**.*......
>    ..............**......
>
> :c/6 spaceship:  A {spaceship} travelling at one sixth of the
>    {speed of light}.  The first such spaceship to be discovered was the
>    {dragon}, found by Paul Tooke in April 2000.  The first diagonally
>    moving example was the {seal}, found by Nicolay Beluchenko in
>    September 2005.  Another orthogonal c/6 spaceship, found by Paul
>    Tooke in March 2006, is shown below.
>    ..*..............*..................................*.....
>    *..*..***.......*.****...............**...........**.*....
>    *..*............***.*.*.........*.....*.......*...*.......
>    .*.*..*.....................***..*.*.***.....*.*.*....*...
>    ..**......*....*................******..*..*...*...*..*...
>    .*.*...**.....*...**......**.**..*..**..*.*.**..*.........
>    ..*.....*.**..*...**......**....*.*.*..*..*.*.*......**..*
>    ..*....***..*.........***.......***.*.**.....*.......***.*
>    ............*********...*........**.***...****.........*.*
>    ..........................................................
>    ............*********...*........**.***...****.........*.*
>    ..*....***..*.........***.......***.*.**.....*.......***.*
>    ..*.....*.**..*...**......**....*.*.*..*..*.*.*......**..*
>    .*.*...**.....*...**......**.**..*..**..*.*.**..*.........
>    ..**......*....*................******..*..*...*...*..*...
>    .*.*..*.....................***..*.*.***.....*.*.*....*...
>    *..*............***.*.*.........*.....*.......*...*.......
>    *..*..***.......*.****...............**...........**.*....
>    ..*..............*..................................*.....
>
1359,1364c1469,1475
<    {metacatacryst}.  The catacryst consists of three {ark}s plus a
<    glider-producing {switch engine}.  It produces a block-laying switch
<    engine every 47616 generations.  Each block-laying switch engine has
<    only a finite life, but the length of this life increases linearly
<    with each new switch engine, so that the pattern overall grows
<    quadratically, as an unusual type of MMS {breeder}.
---
>    {metacatacryst}, and later by {Gotts dots} and {wedge}.  The catacryst
>    consists of three {ark}s plus a glider-producing {switch engine}.  It
>    produces a block-laying switch engine every 47616 generations.  Each
>    block-laying switch engine has only a finite life, but the length of
>    this life increases linearly with each new switch engine, so that
>    the pattern overall grows quadratically, as an unusual type of MMS
>    {breeder}.
1733c1844
<    46 and 60 to replace the {Kok's galaxy}.
---
>    46 and 60 that can be used instead of the {Kok's galaxy}.
2246,2248c2357
<    Paul Tooke in April 2000, was the first known c/6 spaceship.
<    All other known orthogonal c/6 spaceships are {flotilla}s involving
<    at least two dragons.
---
>    Paul Tooke in April 2000, was the first known {c/6 spaceship}.
2433c2542
<    useful examples are the following two small p3 c/3 spaceships:
---
>    useful examples are the following two small p3 {c/3 spaceship}s:
2454c2563
<    a c/4 spaceship can also be self-repairing.  Stephen Silver noticed
---
>    a {c/4 spaceship} can also be self-repairing.  Stephen Silver noticed
3030,3031c3139,3140
<    also a frequent contributor to the blog, which  can be found at
<    {http://gameoflife-news.blogspot.com}.
---
>    also a frequent contributor to the blog, which can be found at
>    {http://pentadecathlon.com/lifeNews/index.php}.
3290,3292c3399,3401
<    March 2003 that Summers and Elkies managed to find a way perform the
<    crucial last step.  Summers then used the new synthesis to build a
<    c/2 forward rake for the 2c/5 spaceship; this was the first example
---
>    March 2003 that Summers and Elkies managed to find a way to perform
>    the crucial last step.  Summers then used the new synthesis to build
>    a c/2 forward rake for the 2c/5 spaceship; this was the first example
3309,3311c3418,3451
< :glider train:  A certain {puffer} that produces two rows of {block}s
<    and two backward {glider} waves.  Ten of these were used to make the
<    first {breeder}.
---
> :glider train:  A certain p64 c/2 orthogonal {puffer} that produces two
>    rows of {block}s and two backward {glider} waves.  Ten of these were
>    used to make the first {breeder}.
>    ..............................*............
>    ...............................*...........
>    .........................*.....*...........
>    ....*.....................******.....******
>    .....*..............................*.....*
>    *....*....................................*
>    .*****..............................*....*.
>    ......................................**...
>    ...........................................
>    .....................................*.....
>    ....................................*......
>    ...................................**...**.
>    ...................................*.*...**
>    ....................................*...**.
>    ........................................*..
>    ...........................................
>    ........................................*..
>    ....................................*...**.
>    ...................................*.*...**
>    ...................................**...**.
>    ....................................*......
>    .....................................*.....
>    ...........................................
>    ......................................**...
>    .*****..............................*....*.
>    *....*....................................*
>    .....*..............................*.....*
>    ....*.....................******.....******
>    .........................*.....*...........
>    ...............................*...........
>    ..............................*............
3372a3513,3521
> :Gotts dots:  A 41-cell pattern with superlinear (but not quadratic)
>    growth.  In terms of initial population, this is the smallest known
>    pattern with superlinear growth.  It was found in March 2006 by
>    Bill Gosper, who named it in honour of Nick Gotts (discoverer of
>    many other low-population superlinear patterns, such as {Jaws},
>    {mosquito}s, {teeth}, {catacryst} and {metacatacryst}).  The
>    population of the pattern at time t is asymptotically proportional
>    to t.log(t).
>
3432,3434c3581,3584
< :grey ship:  A {spaceship} that contains a region with a density of 1/2,
<    and which is {extensible} in such a way that the region of density
<    1/2 can be made larger than any given square region.
---
> :grey ship:  A {spaceship} that contains a region with an average
>    density of 1/2, and which is {extensible} in such a way that the
>    region of average density 1/2 can be made larger than any given
>    square region.
3501c3651
< :hammerhead:  A certain front end for c/2 spaceships.  The central
---
> :hammerhead:  A certain front end for {c/2 spaceship}s.  The central
3572,3586c3722,3734
<    advantage of the considerable amount of repetitive behaviour in many
<    large patterns of interest.  This algorithm is described by Gosper
<    in his paper listed in the bibliography at the end of this lexicon.
<    Roughly speaking, the idea is to store subpatterns in a hash table so
<    that the results of their evolution do not need to be recomputed if
<    they arise again at some other place or time in the evolution of the
<    full pattern.  This does, however, mean that complex patterns can
<    require substantial amounts of memory.
<      Hashlife provides a means of evolving repetitive patterns millions
<    (or even billions or trillions) of generations further than normal
<    Life algorithms can manage in a reasonable amount of time.  It is
<    not, however, suitable for showing a continuous display of the
<    evolution of a pattern, because it works asynchronously - at any
<    given moment it will usually have evolved different parts of the
<    pattern through different numbers of generations.
---
>    advantage of the considerable amount of repetitive behaviour in
>    many large patterns of interest.  It provides a means of evolving
>    repetitive patterns millions (or even billions or trillions) of
>    generations further than normal Life algorithms can manage in a
>    reasonable amount of time.
>      The hashlife algorithm is described by Gosper in his paper listed
>    in the bibliography at the end of this lexicon.  Roughly speaking,
>    the idea is to store subpatterns in a hash table so that the results
>    of their evolution do not need to be recomputed if they arise again
>    at some other place or time in the evolution of the full pattern.
>    This does, however, mean that complex patterns can require
>    substantial amounts of memory.
>      See also {Golly}.
4085,4086c4233,4234
<    common {spaceship}.  Found by Conway in 1970.  See also {LWSS} and
<    {MWSS}.
---
>    common {spaceship}.  Found by Conway in 1970 by modifying a {LWSS}.
>    See also {MWSS}.
4208c4356,4357
<    {sawtooth}s and a {caber tosser}.
---
>    {sawtooth}s and a {caber tosser}.  Another pattern with superlinear
>    but non-quadratic growth is {Gotts dots}.
4328c4477
<    {catacryst} and {metacatacryst}.
---
>    {catacryst}, {metacatacryst}, {Gotts dots} and {wedge}.
4574a4724,4726
> :line-cutting reaction:  A reaction that can cut an infinite diagonal
>    line of cells, leaving a gap with both ends sealed.
>
4808,4809c4960,4961
<    (after the {glider}).  Found by Conway in 1970.  See also {MWSS}
<    and {HWSS}.
---
>    (after the {glider}).  Found by Conway when one formed from a random
>    soup in 1970.  See also {MWSS} and {HWSS}.
4865,4866c5017,5019
<    by Nick Gotts, December 2000.  This is currently the smallest known
<    pattern (in terms of initial population) with superlinear growth.
---
>    by Nick Gotts, December 2000.  This was for some time the smallest
>    known pattern (in terms of initial population) with superlinear
>    growth, but has since been beaten by {Gotts dots} and {wedge}.
5054,5055c5207,5208
<    growth, but it has since been superseded by {teeth}, {catacryst} and
<    {metacatacryst}.
---
>    growth, but it has since been superseded by {teeth}, {catacryst},
>    {metacatacryst}, {Gotts dots} and {wedge}.
5100,5101c5253,5254
<    most common {spaceship}. Found by Conway in 1970.  See also {LWSS}
<    and {HWSS}.
---
>    most common {spaceship}.  Found by Conway in 1970 by modifying a
>    {LWSS}.  See also {HWSS}.
5535a5689,5716
>
> :p72 quasi-shuttle:  The following {oscillator}, found by Jason Summers
>    in August 2005.  Although this looks at first sight like a {shuttle},
>    it isn't really.
>    ..............................*......
>    .............................**......
>    ............................*.**.....
>    .****......................***..*....
>    *....*.......................*.*.*...
>    *...*.*.......................*.*.*..
>    .*...*.*......**...............*..***
>    .......*.....*.*................**.*.
>    .......*.....*...................**..
>    ....*..*.....***.................*...
>    .....**..............................
>    .....................................
>    .....**..............................
>    ....*..*.....***.................*...
>    .......*.....*...................**..
>    .......*.....*.*................**.*.
>    .*...*.*......**...............*..***
>    *...*.*.......................*.*.*..
>    *....*.......................*.*.*...
>    .****......................***..*....
>    ............................*.**.....
>    .............................**......
>    ..............................*......
>
5674c5855
< :phase change:  A {perturbation} of a periodic object which causes the
---
> :phase change:  A {perturbation} of a periodic object that causes the
6060a6242,6243
> :PRNG: = {pseudo-random number generator}
>
6102,6110c6285,6301
< :pseudo-random glider generator:  An object which emits a random-looking
<    stream of {glider}s, like the sequence of bits from a pseudo-random
<    number generator.  Pseudo-random glider generators contain gliders
<    or other {spaceship}s in a loop with a feedback mechanism which
<    causes later spaceships to interfere with the generation of earlier
<    spaceships.  The {period} can be very high, since a loop of n
<    spaceships has 2^n possible states.
<      The first pseudo-random glider generator was built by Bill Gosper.
<    David Bell built the first moving one in 1997, using c/3 {rake}s.
---
> :pseudo-random glider generator:  A {pseudo-random number generator}
>    in which the bits are represented by the presence or absence of
>    {glider}s.  The first pseudo-random glider generator was built by
>    Bill Gosper.  David Bell built the first moving one in 1997, using
>    c/3 {rake}s.
>
> :pseudo-random number generator:  A pseudo-random number generator
>    (PRNG) is an algorithm that produces a sequence of bits that
>    looks random (but cannot really be random, being algorithmically
>    determined).
>      In Life, the term refers to a PRNG implemented as a Life pattern,
>    with the bits represented by the presence or absence of objects such
>    as {glider}s or {block}s.  Such a PRNG usually contains gliders or
>    other {spaceship}s in a loop with a feedback mechanism that causes
>    later spaceships to interfere with the generation of earlier
>    spaceships.  The {period} can be very high, as a loop of n spaceships
>    has 2^n possible states.
6177a6369,6383
>    In April 2006, Jason Summers found a way to make the classic puffer
>    train into a p20 {spaceship} by adding a {glider} at the back:
>    ***...........***.
>    *..*..........*..*
>    *......***....*...
>    *.....*..*....*...
>    .*.*..*...*....*.*
>    .......****.......
>    .........*........
>    ..................
>    ..................
>    ..................
>    .......***........
>    .......*..........
>    ........*.........
6401c6607,6609
<    by Jason Summers in September 2000.  See also {tubstretcher}.
---
>    by Jason Summers in September 2000.  This is the smallest known
>    {c/4 spaceship} other than the {glider}.  This spaceship can also be
>    used to make the smallest known {tubstretcher}.
6491,6492c6699,6700
<    and less symmetric {stator} discovered by Noam Elkies in August
<    1994.  Compare with {Gray counter}.
---
>    and less symmetric {stator} found by Noam Elkies in August 1994.
>    Compare with {Gray counter}.
6752c6960
<    time it has a {population} of 116.
---
>    time it has a {population} of 116, including six {glider}s.
6766c6974,6975
<    (sequence A001511 in The On-Line Encyclopedia of Integer Sequences).
---
>    (sequence A001511 in The On-Line Encyclopedia of Integer Sequences:
>    {http://www.research.att.com/~njas/sequences/A001511}).
6870c7079
< :seal: (c/6 diagonally, p6)  The first c/6 diagonal {spaceship}, found
---
> :seal: (c/6 diagonally, p6)  The first diagonal {c/6 spaceship}, found
7285,7286c7494
<    An end can also be stabilized by killer {candlefrobra}s, although
<    this isn't efficient.
---
>    An end can also be stabilized by killer {candlefrobra}s.
7288c7496
< :snail: (c/5 orthogonally, p5)  The first known c/5 {spaceship},
---
> :snail: (c/5 orthogonally, p5)  The first known {c/5 spaceship},
7453,7460c7661,7664
<    {LWSS}, {MWSS} and {HWSS}.  For further examples see {B29},
<    {big glider}, {brain}, {Canada goose}, {Coe ship}, {Cordership},
<    {crane}, {dart}, {dragon}, {ecologist}, {edge-repair spaceship},
<    {Enterprise}, {flotilla}, {fly}, {hammerhead}, {hivenudger},
<    {non-monotonic}, {Orion}, {puff suppressor}, {pushalong}, {quarter},
<    {Schick engine}, {seal}, {sidecar}, {snail}, {still life tagalong},
<    {sparky}, {swan}, {turtle}, {wasp}, {weekender} and {x66}.  See also
<    {Caterpillar}.
---
>    {LWSS}, {MWSS} and {HWSS}.  See also the entries on individual
>    spaceship speeds: {c/12 spaceship}, {c/6 spaceship},
>    {c/5 spaceship}, {c/4 spaceship}, {2c/7 spaceship}, {c/3 spaceship},
>    {17c/45 spaceship}, {2c/5 spaceship} and {c/2 spaceship}.
7492,7515d7695
<      The following diagram shows one of only two known c/5 diagonal
<    spaceships.  It was found by Jason Summers in January 2005.
<    ..........**..........
<    .........*..*.........
<    ........**............
<    .........*.**.........
<    ..........*.***.......
<    ..........**.***......
<    ............*....**...
<    ............***....**.
<    ..*.........*.*.......
<    .***........*..*......
<    *...**................
<    *..*.*.......**.*..*..
<    .*.**.****...*...****.
<    ....**.*...**.......*.
<    ....**.**..*.........*
<    .....*...*........*.**
<    ...........*.......*..
<    ......*.....*......*..
<    ......*.....*..*......
<    .......*...**...**....
<    .......*....**.*......
<    ..............**......
7571c7751
<    speed at which any effect can propagate.
---
>    speed at which any effect can propagate.  Usually denoted c.
7581c7761
<    {puffer}s, including {rake}s.  See also {pre-pulsar}.
---
>    {puffer}s, including {rake}s.  See also {PPS}.
7657,7658c7837,7841
<    This is not necessarily well-defined, because the eater may have more
<    than one eating action.
---
>    This is not always well-defined, because an eater can have more than
>    one eating action.
>
> :statorless:  A statorless {oscillator} is one in which no cell is
>    permanently on - that is, the {stator} is empty.
7758a7942,7945
> :stream:  A line of identical objects (usually {spaceship}s), each of
>    which is moving in the same direction, this direction being parallel
>    to the line.  Compare with {wave}.
>
7887a8075,8116
> :switch engine channel:  Two lines of {boat}s (or other suitable
>    objects, such as {tub with tail}s) arranged so that a {switch engine}
>    can travel between them, in the following manner:
>    ..............**................
>    .............*.*................
>    ..............*.................
>    ................................
>    ................................
>    ................................
>    ................................
>    ................................
>    .......***............**........
>    ........*..*.........*.*........
>    ............*.........*.........
>    .........*.*....................
>    ................................
>    ................................
>    ................................
>    ................................
>    ..............................**
>    .............................*.*
>    ..............................*.
>    ................................
>    ................................
>    .*..............................
>    *.*.............................
>    **..............................
>    ................................
>    ................................
>    ................................
>    ................................
>    ................................
>    .........*......................
>    ........*.*.....................
>    ........**......................
>    David Bell used this in June 2005 to construct a "bobsled"
>    oscillator, in which a switch engine {factory} sends switch
>    engines down a channel, at the other end of which they are
>    deleted.
>
> :switch engine chute: = {switch engine channel}
>
7909a8139,8166
>      The following {c/4 spaceship} (Nicolay Beluchenko, February 2004)
>    has two wings, either of which can be considered as a tagalong.
>    But if either wing is removed, then the remaining wing becomes an
>    essential component of the spaceship, and so is no longer a tagalong.
>    .......................*.......................
>    .......................*.......................
>    ......................*.*......................
>    ...............................................
>    .....................*...*.....................
>    ....................**...**....................
>    ..................**.*...*.**..................
>    ................**.*.*...*.*.**................
>    ............*...***.*.....*.***...*............
>    ............******...........******............
>    ...........*..*....*.......*....*..*...........
>    ...................*.......*...................
>    ..........***.....................***..........
>    .........*.**.....................**.*.........
>    ........*..*.......................*..*........
>    ........*.............................*........
>    .........**.........................**.........
>    .........**.........................**.........
>    ***......*...........................*......***
>    .*......***.........................***......*.
>    ......**..*.........................*..**......
>    ..**.*.***...........................***.*.**..
>    .*...*.*...............................*.*...*.
>    .*...**.................................**...*.
7950c8207
<    by {catacryst} and {metacatacryst}.
---
>    by {catacryst}, {metacatacryst}, {Gotts dots} and {wedge}.
8045a8303,8321
> :T-nosed p5: (p5)  Found by Nicolay Beluchenko in April 2005.
>    .....**...............**.**.....*........
>    ..*..*.........**.*.***.**......*........
>    .*.*.*.....*....*.*.***......**.*........
>    *..*.*.******.....*....*.*...**.*........
>    .**.*.*..*...***..*.****..*.*.**.**......
>    ..*.*..**.*..*..*.**....***.*.*....**....
>    .*..*...*..*.*.**....***...*.............
>    .*.*.*...***.*...****...*..*.*..**.*..*..
>    **.*.........**.*....*.*.*.*........*.***
>    .*.*.*...***.*...****...*..*.*..**.*..*..
>    .*..*...*..*.*.**....***...*.............
>    ..*.*..**.*..*..*.**....***.*.*....**....
>    .**.*.*..*...***..*.****..*.*.**.**......
>    *..*.*.******.....*....*.*...**.*........
>    .*.*.*.....*....*.*.***......**.*........
>    ..*..*.........**.*.***.**......*........
>    .....**...............**.**.....*........
>
8455,8493c8731,8757
< :tubeater:  A pattern that consumes the output of a {tubstretcher}.  The
<    smallest known tubeater was found by Hartmut Holzwart, and is shown
<    below in conjunction with the smallest known tubstretcher.
<    .......**.........................
<    .......*.*........................
<    .......*..........................
<    ..........*.......................
<    ..........**......................
<    ..........**......................
<    .........**.......................
<    **......**...*....................
<    *.*...**..*.*.*...................
<    *.....***....*.*..................
<    ...*..........*.*.................
<    ...**..........*.*................
<    ................*.*...............
<    .................*.*...*..........
<    ..................**..*.*.........
<    .....................**.*.........
<    .....................**...........
<    .....................**...........
<    ...............................**.
<    .......................*....**.*..
<    .......................***..**....
<    .......................***..**....
<    ........................**........
<    ..................................
<    ..........................*.......
<    .........................**.......
<    .........................*........
<    ..........................*.......
<    ..................................
<    ...........................**.....
<    ............................*.**..
<    ................................*.
<    .............................**...
<    .............................**...
<    ...............................*..
<    ................................**
---
> :tubeater:  A pattern that consumes the output of a {tubstretcher}.
>    The smallest known tubeater was found by Nicolay Beluchenko
>    (September 2005), and is shown below in conjunction with the
>    smallest known tubstretcher.
>    ........*....................
>    .......**....................
>    .......*.*...................
>    .............................
>    ..........**.................
>    ..........**.................
>    .......................***...
>    .*......**...*.........*.....
>    **.....*..*.*.*.........*....
>    *.*...**.*...*.*..........***
>    ....*.........*.*............
>    ...*...........*.*.....**....
>    ...*..*.........*.*....*.*.*.
>    .................*.*...*...**
>    ..................*.....*....
>    ...................*..**..*..
>    .....................*.****..
>    ......................***...*
>    ..........................**.
>    ...........................*.
>    ...........................**
>    ..........................*..
>    ...........................**
8515c8779,8780
< :tub with tail: (p1)
---
> :tub with tail: (p1)  The following 8-cell {still life}.  See {eater}
>    for a use of this object.
8673,8674c8938,8939
<    cell for Wolfram's Rule 100, a one-dimensional {cellular automaton}
<    that is know be universal.
---
>    cell for Wolfram's Rule 110, a one-dimensional {cellular automaton}
>    that is known be universal.
8689,8696c8954,8960
<    Paul Rendell completed a Turing machine construction (described
<    in {http://www.cs.ualberta.ca/~bulitko/F02/papers/tm_words.pdf}).
<    This, however, has a finite tape, as opposed to the infinite tape of
<    a true Turing machine, and is therefore not a universal computer.
<    But in November 2002, Paul Chapman announced the construction
<    of a universal computer, details of which can be found at
<    {http://www.igblan.free-online.co.uk/igblan/ca/}.  This is
<    a universal register machine based around Dean Hickerson's
---
>    Paul Rendell completed a Turing machine construction (see
>    {http://rendell-attic.org/gol/tm.htm} for details).  This, however,
>    has a finite tape, as opposed to the infinite tape of a true Turing
>    machine, and is therefore not a universal computer.  But in November
>    2002, Paul Chapman announced the construction of a universal
>    computer, see {http://www.igblan.free-online.co.uk/igblan/ca/}.
>    This is a universal register machine based around Dean Hickerson's
8813a9078,9093
> :Wainwright's tagalong:  A small p4 c/4 diagonal {tagalong} that has 7
>    cells in every phase.  It is shown here attached to the back of a
>    {Canada goose}.
>    ***.............
>    *.........**....
>    .*......***.*...
>    ...**..**.......
>    ....*...........
>    ........*.....*.
>    ....**...*...**.
>    ...*.*.**....*.*
>    ...*.*..*.**.*..
>    ..*....**.....*.
>    ..**............
>    ..**............
>
8843a9124,9127
> :wave:  A line of identical objects (often {spaceship}s), each of
>    which is moving in the same direction, this direction not being
>    parallel to the line.  Compare with {stream}.
>
8860a9145,9148
> :wedge:  A 26-cell quadratic growth pattern found by Nick Gotts in March
>    2006, based on {Gotts dots}.  In terms of its initial population,
>    this is the smallest known pattern with superlinear growth.

A lot has happened since 2007, and there are a lot of casual references in various Lexicon definitions to things which are no longer quite true. Look at the first item in the diff file, for example:

:17c/45 spaceship: A {spaceship} travelling at seventeen forty-fifths of the {speed of light}. This is the strangest spaceship speed for which there is any known example...

Nowadays we have quite a number of strange speeds, and no particularly good candidate for the strangest. There are similar no-longer-true statements scattered all through the Lexicon, and it's going to take a very careful reading to find them all.

By this time, the LifeWiki has clearly taken over as the most up-to-date and (mostly) authoritative reference for Life terminology. But Golly is still packaged with the old Life Lexicon, which is still pretty useful just as it is -- or it would be if it were just a little more reliable, anyway.

I'm thinking that in 2016 I'd like to put together a tenth-anniversary update, to patch up any obvious inaccuracies in existing Life Lexicon entries.

As a secondary goal, I wouldn't mind adding any new terms that have cropped up in the last decade, that have really proven themselves to be useful. As a simple rule of thumb, let's say that I'll probably add a new term if an entry for it has already existed in the LifeWiki for a year or two ... asssuming that that entry doesn't have a header suggesting that it's non-notable.

A new definition is much more likely to make it into the tenth-anniversary update if a nice clear simple short Lexicon-compatible text definition shows up in a message in this thread. LifeWiki definitions are often longer than the Life Lexicon can support, and will need to be boiled down to the basics, with extra references and illustrations removed. Bonus points if the odd format of the original text Lexicon is followed exactly. The term is delimited by colons --

:new term:

-- and references to {other terms in the Lexicon} are marked off in {curly braces}. Quoted patterns are in ASCII format -- .=OFF, *=ON -- indented by four spaces.

As usual, I reserve the right to arbitrarily change the rules for accepting and rejecting proposed entries to the Lexicon tenth-anniversary update, as long as I'm the one doing the work of sorting and editing and deciding the details. On the other hand, since the Life Lexicon can be copied and distributed under the Creative Commons Attribution-ShareAlike 3.0 Unported licence (CC BY-SA 3.0), anyone else is very much welcome to take over doing all that work instead of me, and I'll be very grateful.
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Re: Life Lexicon update

Postby gameoflifeboy » December 30th, 2015, 7:30 pm

The References page in Golly Help still contains links to code.google.com/p/ruletablerepository, calcyman.awardspace.co.uk, home.interserv.com/~mniemiec, and other outdated links. These links should be updated in the next version of golly.

Also, the LifeWiki Golly pattern archives don't seem to have been updated for years, unlike the normal pattern archives. There is no place in Golly's online archives many of the newer discoveries can be found.
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Posts: 456
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Re: Life Lexicon update

Postby dvgrn » January 1st, 2016, 11:17 am

gameoflifeboy wrote:The References page in Golly Help still contains links to code.google.com/p/ruletablerepository, calcyman.awardspace.co.uk, home.interserv.com/~mniemiec, and other outdated links. These links should be updated in the next version of golly.

Also, the LifeWiki Golly pattern archives don't seem to have been updated for years, unlike the normal pattern archives. There is no place in Golly's online archives many of the newer discoveries can be found.

Thanks -- good to have the reminder here. I'll tackle those items when I get a chance.

Update notes so far on Life Lexicon pages A through E (plus the numeric page):

Remove “14-ner”, “2 eaters”, move “4 boats” to “four boats”

:1G seed:  See {seed}.

:(23,5)c/79:  TBD (by analogy to :17c/45: in the diff file posted previously)

:25-cell quadratic growth:  TBD
:26-cell quadratic growth: -- maybe?

:31c/240:  TBD

:56P6H1V0: A 56-cell spaceship discovered by Hartmut Holzwart in 2009, the smallest known c/6 orthogonal spaceship as of this writing.

:60P5H2V0: A 60-cell 2c/5 spaceship discovered by Tim Coe in May 1996.  It was the first non-c/2 orthogonal spaceship to be successfully constructed via {glider synthesis}.

:anteater:  +Matthias Merzenich discovered a c/5 anteater on 15 April /2011.  Connecting this to a standard diagonal {antstretcher} created a new oblique {wavestretcher} (a type of {growing spaceship}) and also an alternate {space nonfiller} mechanism.

.......................................................o.....
.......................................................oo....
.....................................................o..o....
....................................................o........
.................................................oo..o.......
................................................o..o.........
.................................................o...........
.............................................o...oo..........
............................................o.oo.............
...........................................oo..o.............
...........................................oo.oo.............
...........................................o..o..oo..........
..........................................oo......oo.........
...........................................o.oo.o.oo.........
..........................................o.ooo.o............
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.....................................o.......................
..................................oooo.......................
................................o.oo.o.......................
.....................................o.......................
................................o............................
.................................o..o........................
...................................o.........................
.........................o....ooo....................ooo.....
oo......................o.ooo....o......................o...o
..oo.oo.................o..o....o....................o...o...
..oo...oo.oo...............o..o................oo.o...o.oooo.
oo.....oo...oo.oo.........oo.ooo...oo..oo.ooo.o....o.....o..o
.....oo.....oo...oo.oo......o.oo..o.o..ooo.oo.o.o...o......o.
..........oo.....oo...oo.o...o....o.o.o..oo..o..o...oooo.....
...............oo.....oo..o.o.oo..o..o.......................
....................oo...........o....o..........oo...oo.....
.......................................o..........o..........
....................................o........................
....................................oo.......................

A supporting c/5 {spark} is required at the right edge.  It can be supplied by a {spider} or another c/5 orthogonal spaceship with a similar {side spark}.


:antstretcher: -- Add Nicolay Beluchenko and Hartmut Holzwart’s example from 11 Jan 2006:

......................................................oo.......
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..................................................oo...oo.oooo.
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...............................oo..........................o...
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..........................o....ooo...................o..ooo....
.........................ooooo.ooo..o.oo................oo.....
.........................o..oo......o...oo.oo.........oo.oo....
...................................o....oo...oo.oo.......oo....
...........................oo..oo.oo..oo.....oo...oo.o.o.......
...................................o.......oo.....oo...........
.....................ooo...o.....oo.............oo....o........
.....................o.....o..o.oo...................o.........
......................o...oo.o.................................
.........................oo...o.o..............................
.............ooo..........o....................................
.............o.....ooo..oo.....................................
..............o..oo.ooo.oo.....................................
................o..........o...................................
.................o.o.oo....o...................................
...................oo.o........................................
.................oo...o.o......................................
................oo.............................................
..................o............................................
...............oo..............................................
..............ooo..............................................
.............oo.o..............................................
............oooo.o.............................................
.................ooo...........................................
..................oo...........................................
..........ooo.oo...............................................
.........o...ooo...............................................
............ooo................................................
........o.o.o..................................................
.......oooo....................................................
.......o.......................................................
........oo.....................................................
.........o..o..................................................
oo.............................................................
o.o...ooo......................................................
o...o....o.....................................................
...oo..........................................................
...o.....o.....................................................


:Bellman:  a program for searching catalytic reactions, developed by Mike Playle, which successfully found the {Snark}.

:boat-bit:  move “In January 1997…” below the pattern.

:block pusher: -- add context from construction arm mechanisms?

:boojum reflector:  -- no longer the smallest known.  It was the smallest and fastest known stable reflector until the discovery of the {rectifier} in 2009.

:construction arm:  TBD

:crab:  See {quarter}.

:quarter:  +the name is due to the minimum population of 25 cells.

:one per generation:  See {quarter}

x = 17, y = 15, rule = b3/s23
8b2o7b$7b2o8b$9bo7b$11b2o4b$10bo6b2$9bo2b2o3b$b2o5b2o4bo2b$2o5bo5bo3b$
2bo4bobo3b2o2b$4bo2bo4b2obob$4b2o7b2o2b$8bo4bob2o$7bobo2bob2ob$8bo!

:catacryst: -- mention newest superlinear growth patterns -- {wedge grow}, {26-cell quadratic growth}, and {25-cell quadratic growth}.

Is :Caterpillar: still _by far_ the largest and most complex pattern ever constructed?  Just in terms of population, not bounding box, correct?

:clock insertion:  a uniquely effective method of adding a glider to the front edge of a {salvo}, by first constructing a {clock}, then converting it to a glider using a one-bit {spark}.

:Coe ship: mention that it’s the first non-p4 spaceship ever seen emerging from an asymmetrical random {soup} configuration.

:colour-preserving: See {colour of a glider}.  A {Snark} is a colour-preserving reflector.
:colour-changing: See {colour of a glider}.  The period-8 reflector shown in {reflector} is colour-changing, as are its p4/5/6/7 and higher-period versions.

-- Actually, I still want to make separate {p5-8 reflector} entries.  Include more exotic periods, or no?  How about p4 -- what was the deal with that again?

:colorized Life: -> colourised?

:conduit: -- add something about the number of conduits now available.

:construction envelope: the region affected by an active reaction, such as a {glider construction} of an object.  The envelope corresponds to the state-2 blue cells in {LifeHistory}.  See also {edgy}.

:LifeHistory:  A multistate CA rule equivalent to two-state B3/S23 Life, but with several additional states intended for annotation purposes.  A “history” state records whether an off cell has ever turned on in the past, and other states allow on and off cells to be permanently or temporarily marked, without affecting the evolution of the pattern.

-- Possibly replace {converter} example with a modern stable X-to-*WSS converter?

:dart: A 25-glider recipe for the dart was found in December 2014, making it the first glider-constructible c/3 spaceship.

:double wing: +The term is no longer in use.

:dove: Found in 2015 to be a possible active reaction for the input or output of a {converter}.

:dragon:  Remove “All other known orthogonal c/6 spaceships are flotillas involving at least two dragons”... With 102 cells, it was the smallest known orthogonal c/6 spaceship until Hartmut Holzwart discovered {56P6H1V0} in April 2009.

:drain trap: +The term is no longer in use.

eater(2): “two different directions” is an odd way of putting it -- that’s more the TWIT-eater’s specialty. Update the TWIT pattern to show this, and give it its own entry, adding Chris Cain’s Spartan from-the-side eater also.

eater2: “Can eat gliders arriving on any of four adjacent {lane}s.”

:edgy:  in slow-salvo terminology, an “edgy” glider construction recipe is one that places its final product at or very near the edge of its construction envelope.

remove :eaters +:

:egg:  +The term is no longer in common use.

:envelope: {construction envelope}

:Gemini: The first {self-constructing} spaceship, and also the first {oblique} spaceship, traveling at a speed of (5120,1024)c/33699586.  It was made public by Andrew Wade on 18 May 2010.  It was the thirteenth explicitly constructed spaceship velocity in Life, and made possible an infinite family of related velocities.  The Gemini spaceship derives its name from the Latin “gemini”, meaning twins, describing its two identical halves, each of which contains three Chapman-Greene {construction arms}. A tape of gliders continually relays between the two halves, instructing each to delete its parent and construct a daughter configuration.

-- Add links to other Caterpillar-type constructions:  {Centipede}, {waterbear}, {31c/240}?, {shield bug}?, {half-baked knightship}, {Parallel HBK}

:highway robber: any mechanism that can retrieve a signal from a spaceship {lane} while allowing spaceships on nearby lanes to pass by unaffected.  In practice the spaceship is generally a glider.  The signal is removed from the lane, an output signal is generated elsewhere, and the highway robber returns to its original state.  A competent highway robber does not affect gliders even on the lane adjacent to the affected glider stream, except during its recovery period.

A perfect highway robber doesn’t affect later gliders even in the lane to which it is attached, even during its recovery period.  Here’s a near-perfect highway robber “bait” that requires three synchronized signals to rebuild (the {Herschel}, {B-heptomino}, and {glider}.)

......................o...........o.........
......................ooo.......o.o.........
.........oo...oo.........o.......oo.........
.........oo...oo........oo..................
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..oo........................................
...o........................................
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.........ooo..........o.o...............oo..
.........o.o............o...................
.........o.....................oo.o.......o.
...............................o.oo......ooo
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..................oo........................

:lane:  a path traveled by a glider, or less commonly, a spaceship such as a loafer.  The lane is centered on the line of symmetry (if any) of the spaceship in question.  If a lane is clear, then the spaceship can travel along it without colliding or interfering with any other objects.

Diagonal lanes are often numbered consecutively, in half-diagonals ({hd}).  Occasionally diagonal lane measurements are given in quarter-diagonals ({qd}), in part because diagonally symmetric spaceships have a line of symmetry 1qd away from the lines available for gliders.  It’s also convenient that moving a glider forward by 100qd (for example) has the same effect as evolving the same glider for 100 ticks.

:linear propagator: a self-replicating pattern in which each copy of a pattern produces one child that is an exact copy of itself.  The child pattern then blocks the parent from any further replication.   An example was constructed by Dave Greene on 23 November 2013.  By some definitions, due to its limited one-dimensional growth pattern, the linear propagator is not a true replicator, Compare {quadratic replicator}.

:loafer: a c/7 spaceship discovered by Josh Ball on 17 February 2013:

.oo..o.oo
o..o..oo.
.o.o.....
..o......
........o
......ooo
.....o...
......o..
.......oo

It has a known 8-glider construction {recipe}, probably not minimal, discovered on the following day:

.................................o
...............................oo.
................................oo
.........o........................
.o........o.......................
..o.....ooo.......................
ooo...............................
..................................
..................................
.....o............................
......o...........................
....ooo...........................
........................o.o.......
.........................oo.......
.........................o........
..................................
...........................o.o....
...........................oo.....
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...............................ooo
...............................o..
................................o.
..................................
..................................
..................................
..................................
..................................
..................................
.....oo...........................
......oo..........................
.....o............................

The loafer was therefore the first new glider-constructible spaceship in almost a decade.  (A glider synthesis for a 2c/5 ship, 60P5H2V0, was found in March 2003.)

:nonfiller: See {space nonfiller}

:rectifier:  Smallest and fastest known stable 180-degree reflector, with a repeat time of 106.  Was the smallest stable reflector until the discovery of the {Snark} in 2013.

:quadratic replicator:  A pattern that fills all or part of the Life plane by making copies of itself in a nonlinear way.  Small quadratic replicators are known in other Life-like rules, but no example has been found or constructed in Conway’s Life as of January 2016.

:quadratic growth: See {superlinear growth}.

:salvo: A collection of spaceships, usually gliders, all traveling in the same direction.  Any valid glider construction {recipe} can be partitioned into no more than four salvos.  Compare {flotilla}.

:seed:  A {constellation} of still lifes and/or oscillators, which can be converted into another Life object when it is struck by one or more gliders.  Usually the resulting object is a rare still life or spaceship, more complex than the original constellation.  {Spartan} single-glider (1G) seeds are more commonly seen than multi-glider seeds, because a 1G seed can be readily constructed and {trigger}ed using a {slow salvo}.

:semi-Snark:  A small 90-degree glider reflector requiring two input gliders on the same lane for each output glider.  It was discovered by ‘Guam’ on 1 July 2013, using a custom-written search utility.  It functions as a very compact {period doubler} in signal circuitry -- see for example {linear propagator}.

:space nonfiller:  Any pattern that expands indefinitely to affect every cell in the Life plane, but leaves an expanding region of {vacuum} at its center.  Compare {spacefiller}; see also {antstretcher}.  The first nonfiller was discovered by Jason Summers on 14 April 1999:

...................ooo...............
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............o..o.o...o....o..o.......
............o..o.o...o....o..o.......
..........o..........o..o.o.ooo......
..........oo..oo..o.o....o.....o.....
........o................oo..ooo.....
........ooo.o.oo..........o......o...
......o........o.........o.o...ooo...
......ooo.....o..........o........o..
...o.o.........................o.ooo.
..ooooo.o..........................o.
.oo......o.....................ooooo.
oo....oo..................o.o........
.o.o...o..o...............o..o...o.o.
........o.o..................oo....oo
.ooooo.....................o......oo.
.o..........................o.ooooo..
.ooo.o.........................o.o...
..o........o..........o.....ooo......
...ooo...o.o.........o........o......
...o......o..........oo.o.ooo........
.....ooo..oo................o........
.....o.....o....o.o..oo..oo..........
......ooo.o.o..o..........o..........
.......o..o....o...o.o..o............
.......o..o....o...o.o..o............
........ooo....o......ooo............
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...............ooo...................

:swimmer lane:  See {bobsled}.

:Snark: A small stable 90-degree glider reflector with a repeat time of 43 ticks, discovered by Mike Playle on 25 April 2013 using a search utility he wrote called {Bellman}. Compare {boojum reflector}.  Four common Snark variants are shown below -- Playle’s original (top), and variants by Heinrich Koenig, Simon Ekström, and Shannon Omick (left, bottom, and right, respectively):

.............................oo....................
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....ooo............o.o.......o.o............ooo..o.
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:superlinear growth:  TBD (applies to population growth, e.g., for {breeders} and {spacefillers}, and also to the reproduction rate of a {replicator}.  Due to limits enforced by the {speed of light}, no finite pattern can grow at a rate faster than quadratic.)

:TWIT:  {tub-with-tail}

:wave:  TBD

:wavestretcher:  TBD

-- Obviously these aren't just fixes for existing items beginning with A through E. Whenever a new definition was needed as part of an update, I added the word at the bottom of the list, and usually tried to include a quick definition while I was at it. I'll review these again before I continue on with F through Z, and update the above text.

Meanwhile, any comments on the above, or pointers to other outdated details in A through E -- or in F through Z, for that matter -- would be much appreciated. I could use some help on the TBD items like "superlinear growth", for example. It's easy to write long convoluted definitions, but I'm not so good at short simple ones...!
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Re: Life Lexicon update

Postby dvgrn » January 28th, 2016, 2:11 am

Whew. Made it -- have now read pretty much every entry from Achim's p144 to zweiback, looking for anachronisms. There's still a month to go before the ten-year anniversary, but I've added a lot of To Be Done notes to myself where new definitions are needed. Will just have to see how many I can get done by my arbitrary deadline.

The following isn't actually quite a complete copy of my current notes, but it's all that will fit in a single post. Will probably repost again in two parts, after another few weeks of work. Comments and suggestions welcome.

[see later posts for a more up-to-date snapshot]
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Re: Life Lexicon update

Postby calcyman » January 28th, 2016, 12:52 pm

Very impressive!

Golly probably deserves its own entry, as does the Simkin glider gun.
What do you do with ill crystallographers? Take them to the mono-clinic!
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Re: Life Lexicon update

Postby dvgrn » January 28th, 2016, 1:36 pm

calcyman wrote:Very impressive!

Golly probably deserves its own entry, as does the Simkin glider gun.

There's an existing entry for Golly, but of course the Simkin glider gun doesn't have one. I should maybe clarify that the above is just a list of planned changes and additions to the 2006 Lexicon -- it's definitely not the whole thing.

Maybe it's also worth mentioning this again:

dvgrn wrote:A new definition is much more likely to make it into the tenth-anniversary update if a nice clear simple short Lexicon-compatible text definition shows up in a message in this thread.

As soon as I can find the time, I'll post a complete draft copy -- new definitions interspersed with old ones in proper alphabetical order. Suggestions and (especially) contributions of actual definitions will be most welcome. I'm pretty quick at editing, but it's really nice to have something more than just "TBD" to start from.

I'd like to have as many actual patterns included as possible, as long as they're under the Lexicon maximum size of 64x64. One pattern per definition, usually. Any definition that really needs two patterns... should probably be two definitions. If RLE gets posted here, that's fine -- I have a script to convert it to ASCII picture format.
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Re: Life Lexicon update

Postby dvgrn » February 10th, 2016, 10:54 pm

dvgrn wrote:Suggestions and (especially) contributions of actual definitions will be most welcome. I'm pretty quick at editing, but it's really nice to have something more than just "TBD" to start from.

Haven't been getting a lot of contributions yet, but it's not too late... and I've been making decent progress anyway. Going to get the project done with y'all or without you.

I'm up to fifty or sixty pages of new definitions. Mostly the page count has gone up because I've been adding the actual ASCII picture-format diagrams for new stuff like the syringe, and older things like the Fx119 inserter which maybe weren't quite so mainstream in 2006.

It is becoming obvious that there's a huge bias in my choice of new terms to add: I'm adding terms that I can define quickly and clearly without spending too much time on research. So a lot of terms are useful in discussing self-constructing circuitry... or at least I've found them to be useful! I've tried not to add terms unless I've seen them used in several conversations or projects.

Used by someone other than me, that is.

-- Yes, some of my projects have more or less consisted of me talking to myself in a forum thread... including this thread, I suppose, for the most part. But I'm still holding out hope that the definition donations will pick up toward the end.

Here are all the A through H additions so far:

Remove “14-ner”, “2 eaters”, move “4 boats” to “four boats”

:1G seed:  See {seed}.

:(23,5)c/79:  The rate of travel of the {Herschel climber} reaction used in the {self-supporting} {waterbear} {knightship}.

:24-cell quadratic growth: A 39786×143 {quadratic growth} pattern found by Michael Simkin in October 2014, two days after {25-cell quadratic growth} and a week before {switch-engine ping-pong}.

:25-cell quadratic growth:  A 25-cell quadratic growth pattern found by Michael Simkin on October 2014, with a bounding box of 21372×172. It was the smallest-population quadratic growth pattern for two days, until the discovery of {24-cell quadratic growth}. It superseded {26-cell quadratic growth}, which had held the record for eight years.

:26-cell quadratic growth:  a quadratic growth pattern found by Nick Gotts in March 2006, using ideas found in {metacatacryst} and {Gotts dots}.  It held the record for the smallest-population quadratic growth pattern for eight years, until it was surpassed by {25-cell quadratic growth}.

:31c/240:  The rate of travel of the {Herschel-pair climber} reaction used in the {Centipede} and {shield bug} {macro-spaceship}s.

:56P6H1V0: A 56-cell spaceship discovered by Hartmut Holzwart in 2009, the smallest known c/6 orthogonal spaceship as of this writing (March 2016).

:60P5H2V0: A 60-cell 2c/5 spaceship discovered by Tim Coe in May 1996.  It was the first non-c/2 orthogonal spaceship to be successfully constructed via {glider synthesis}.

:anteater:  +Matthias Merzenich discovered a c/5 anteater on 15 April /2011.  Connecting this to a standard diagonal {antstretcher} created a new oblique {wavestretcher} (a type of {growing spaceship}) and also an alternate {space nonfiller} mechanism.

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   oo.....oo...oo.oo.........oo.ooo...oo..oo.ooo.o....o.....o..o
   .....oo.....oo...oo.oo......o.oo..o.o..ooo.oo.o.o...o......o.
   ..........oo.....oo...oo.o...o....o.o.o..oo..o..o...oooo.....
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A supporting c/5 {spark} is required at the right edge.  It can be supplied by a {spider} or another c/5 orthogonal spaceship with a similar {side spark}.

:antstretcher: -- Add Nicolay Beluchenko and Hartmut Holzwart’s example from 11 Jan 2006:

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:ark: +fix the thing about “five known arks”, wherever that was

:arm:  +See also {construction arm}.

:armless: A method of generating {slow salvo}s across a wide range of lanes without using a {construction arm} with a movable {elbow}.  Instead, streams of gliders on two fixed opposing {lanes} collide with each other to produce clean 90-degree output gliders.  Slowing down one of the streams by 8N ticks will move the output lanes of the gliders toward the source of that stream by N {full diagonal}s.  This construction method was used to create the supporting slow salvos in the {half-baked knightship}s, and also in the {Parallel HBK gun}.

:B59H:  One of the earliest and most remarkable {converter}s, discovered by Dave Buckingham in July 1996.  In 59 generations it transforms a B-heptomino into a clean Herschel with very good clearance, allowing easy connections to other conduits.  It forms the final stage of many of the known {composite conduit}s, including the majority of the original sixteen {Herschel conduit}s.  Here a {ghost Herschel} marks the output location:

x = 24, y = 14, rule = B3/S23
b2o$2bo$bo$b2o6$o3b2o15bo$2o2b2o15bo$b2o18b3o$bo21bo$o!

:B60:  A {Herschel conduit} discovered by Michael Simkin in 2015 using his search program, {CatForce}.  It is one of two known {Blockic} Herschel conduits.  After 60 ticks, it produces a Herschel rotated 180 degrees at (x,y) relative to the input.  It can most easily be connected to another B60 conduit, producing a closed loop, the {Simkin glider gun}.

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:B-track:  -The term is more-or-less synonymous with Herschel track
A B-heptomino becomes a Herschel plus a block in twenty generations, so this term was nearly synonymous with {Herschel track} until the discovery of {elementary conduits} that convert a B directly to another B, or to some other non-Herschel signal output.  See for example {BRx46B}.

:Bellman:  a program for searching catalytic reactions, developed by Mike Playle, which successfully found the {Snark}.

:boat-bit:  move “In January 1997...” below the pattern.

:block pusher: -- add context from construction arm mechanisms?

:boojum reflector:  -- no longer the smallest known.  It was the smallest and fastest known stable reflector until the discovery of the {rectifier} in 2009.

:Bx125: One of the original sixteen {Herschel conduit}s, discovered by Paul Callahan in November 1998.  After 125 ticks, it produces an inverted {Herschel} rotated 180 degrees at (-9, -17) relative to the input.  Its {recovery time} is 166 ticks.  A {ghost Herschel} in the pattern below marks the output location:

   ...........................o..........
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:Bx222: One of the original sixteen {Herschel conduit}s, discovered by Paul Callahan in October 1998.  After 222 ticks, it produces a backward-traveling inverted {Herschel} at (6, -16) relative to the input.  Its {recovery time} is 271 ticks.  A {ghost Herschel} in the pattern below marks the output location:

   .............o............................
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:catacryst: +mention newer superlinear growth patterns -- {wedge grow}, {26-cell quadratic growth}, {25-cell quadratic growth}, {24-cell quadratic growth}, and {switch-engine ping-pong}.

:Catagolue: An online database of objects in Conway's Game of Life and similar cellular automata, set up by Adam P. Goucher in 2015. It gathers data from a distributed search of random initial configurations and records the eventual decay products.  Within a year of operation it had completed a census of the {ash} objects from over two trillion asymmetric 16x16 soups, which can be found at at http://catagolue.appspot.com .

:CatForce:  An optimized search program written by Michael Simkin in 2015, using brute-force enumeration of small {Spartan} objects in a limited area, instead of a depth-first tree search.  One major purpose of CatForce is to find glider-constructible completions for signal conduits.  An early CatForce discovery was the {B60} conduit, which enabled a record-breaking new glider gun.

:Centipede:  the smallest known {31c/240} spaceship, constructed by Chris Cain on September 4, 2014.

:Caterpillar: is it still _by far_ the largest and most complex pattern ever constructed?  Just in terms of population, not bounding box, correct?

-- Add links to other Caterpillar-type constructions:  {Centipede}, {waterbear}, {31c/240}?, {shield bug}?, {half-baked knightship}, {Parallel HBK}

:circuit:  Any combination of {conduit}s or {converter}s that moves or processes an active signal.  This includes components with multiple states such as {period multiplier}s or {switch}es, which can be used to build {logic gate}s, {universal constructor}s, and other computation or construction circuitry.

:clearance:  In signal circuitry, the distance from an {edge-shooter} output lane to the last unobstructed lane adjacent to the edge-shooter circuitry.  For example, an {Fx119 inserter} has an unusually high 27{hd} clearance:

:clock insertion:  a uniquely effective method of adding a glider to the front edge of a {salvo}, by first constructing a {clock}, then converting it to a glider using a one-bit {spark}.  Here it rebuilds a sabotaged eater in a deep pocket between other gliders:

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In 2015 Chris Cain used this reaction to demonstrate conclusively that any unidirectional glider {salvo}, no matter how large or tightly packed, can be constructed by collisions between gliders that are initially separated by any finite distance.  As a corollary, because all glider syntheses are made up of two to four unidirectional salvos, any glider-constructible object has a synthesis that starts with every glider at least N cells away from every other glider (for any chosen N).

:Coe ship: +mention that it’s the first non-p4 spaceship ever seen emerging from an asymmetrical random {soup} configuration.

:colour-preserving: See {colour of a glider}.  A {Snark} is a colour-preserving reflector.

:colour-changing: See {colour of a glider}.  The period-8 reflector shown in {reflector} is colour-changing, as are its p4/5/6/7 and higher-period versions.

:component: A partial {glider synthesis} that can be used in the same way in multiple {recipe}s.  A component transforms part of an object under construction in a well-defined way, without affecting the rest of the object.  For example, this well-known component can be used to add a {hook} to any object that includes a protruding {table} end, converting it to a {long bookend}:

   .......o...................o...................o
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:composite:  See {composite conduit}.

:composite conduit:  A signal-processing {conduit} that can be subdivided into two or more {elementary conduits}.

:compression: See {recovery time}.

:colorized Life: -> colourised?

:conduit: +[add something about the number of conduits now available.  Remove sample conduit, move to {B59H} in standard orientation.]

:conduit 1: {B59H}.

:construction arm:  An adjustable mechanism in a {universal constructor} that allows new objects to be constructed in any chosen location that the arm can reach.  A construction arm generally consists of a {shoulder} containing fixed guns or edge shooters, a movable {construction elbow} that slides forward and backward along the {construction lane}(s), and in the case of {single-arm} universal constructors, a {hand} target object at the construction site that can be progressively modified by a {slow salvo} to produce each desired object.

:construction elbow:  One of the components of a {construction arm} in a {universal constructor}.  The elbow usually consists of a single {Spartan} still life or small constellation.  It accepts {elbow operation} {recipe}s, in the form of {salvo}s coming from the construction arm’s {shoulder}.

These recipes may do one of several things:  1) {pull} the elbow closer to the shoulder, 2) {push} the elbow farther from the shoulder, 3) emit a glider or other {spaceship} on a particular output {lane} (while also optionally pushing or pulling the elbow); 4) create a “{hand}” target block or other useful object to one side of the {construction lane}; 5)  duplicate the elbow, or 6) destroy the elbow.

If a mechanism can be programmed to generate recipes for at least the first three options listed above, it is generally capable of functioning as a {universal constructor}.  The main requirement is that push and pull {elbow operations} should be available that are either minimal (1{fd}) or the distances should be relatively prime.

Depending on the {elbow operation} library, there may be only one type of elbow, or there may be two or more elbow objects, with recipes that convert between them.  The {9hd} library had just one elbow type, a block.  The original {10hd} library had two elbows, blocks in mirror-symmetric locations; this was expanded to a larger list for the {10hd Demonoid}.  The {0hd Demonoid} also has a multi-elbow recipe library.

If only one color, parity, or phase of glider can be emitted, then the mechanism will be limited to producing {monochromatic salvo}s or {monoparity salvo}s.  These are less efficient at most construction tasks, but are still generally accepted to enable {universal toolkit}s.  See also {half-baked knightship}.

:construction envelope: the region affected by an active reaction, such as a {glider construction} of an object.  The envelope corresponds to the state-2 blue cells in {LifeHistory}.  See also {edgy}.

:construction lane:  Part of a {construction arm} between the {shoulder} and the {elbow} -- in particular, one of the fixed {lane}s that {elbow operation} signals travel on.  All known {universal constructor}s have used arms with two or more construction lanes, except for the {0hd Demonoid} and {single-lane construction} recipes.

:crab:  See {quarter}.

:converter:  +The following diagram shows a multi-stage {B-heptomino} to {Herschel} to {MWSS} to {glider} converter.  {Ghost Herschel}s mark the inputs and outputs of the {R64} {Herschel conduit}s.  The first stage is {B59H}, the Herschel-to-MWSS stage was discovered by Tanner Jacobi in October 2015, and the MWSS-to-glider stage was found by Matthias Merzenich in July 2013:

x = 48, y = 62, rule = B3/S23
34b2o$35bo3b2o$34bo4b2o$34b2o$36bo$34b3o$33bo$33b2o11$7b2o30b3o$7b2o
30bo2bo$39bo$39bo3bo$b2o36bo$b2o37bobo$5b2o$5b2o15bo$22bo22bo$22b3ob2o
16bobo$24bob2o16bobo$2o43bo$2o7$14b2o27bo$14bo27bobo$12b3o27b2o7$24bo
21b2o$24b3o18b2o$26bo15b2o2b2o$26bo15b2o3bo4$5b2o$5b2o21b2o$11b2o15bo
16b2o$11b2o16b3o14bo$31bo13bo$45b2o$9b2o$9b2o5b2o$16b2o!

:dart: +A 25-glider recipe for the dart was found in December 2014, making it the first glider-constructible c/3 spaceship.

:Demonoid:  The first self-constructing diagonal spaceship. A 0{hd} Demonoid was completed by Chris Cain in December 2015, shortly after a much larger 10{hd} version constructed the previous month in collaboration with Dave Greene. The 0hd spaceship fits in a bounding box about 55,000 cells square, and displaces itself by 65 cells diagonally every 438,852 generations.

The first 0hd Demonoid was fired by a gun.  As of this writing (2016) this is the only case where a spaceship’s gun pattern was completed before the first appearance of the actual spaceship.

:dependent conduit:  A {Herschel conduit} in which the input {Herschel} interacts with catalysts in the first few ticks -- technically at T=-3, before the Herschel is completely formed.  Compare {independent conduit}.  The Herschel is prevented from emitting its {first natural glider}, This is useful in cases where the previous conduit cannot survive a first natural glider emitted from its output Herschel.

This term is somewhat confusing, since it is actually the previous conduit that depends on the dependent conduit to suppress the problematic glider.  Dependent conduits such as the {F166} and {Lx200} do not actually depend on anything.  They can be freely connected to any other conduits that fit, as long as the output Herschel evolves from its standard great-grandparent.  As of this writing, the {Fx158} is the only known case where a conduit’s output Herschel has an alternate great-grandparent, which is incompatible with dependent conduits’ initial transparent block.

:double wing: +The term is no longer in use.

:dove: Found in 2015 to be a possible active reaction for the input or output of a {converter}.

:dragon:  Remove “All other known orthogonal c/6 spaceships are flotillas involving at least two dragons”... With 102 cells, it was the smallest known orthogonal c/6 spaceship until Hartmut Holzwart discovered {56P6H1V0} in April 2009.

:drain trap: +The term is no longer in use.

eater(2): “two different directions” is an odd way of putting it -- that’s more the TWIT-eater’s specialty. Update the TWIT pattern to show this, and give it its own entry, adding Chris Cain’s Spartan from-the-side eater also.

eater2: +“Can eat gliders arriving on any of four adjacent {lane}s.”

:edgy:  in slow-salvo terminology, an “edgy” glider construction recipe is one that places its final product at or very near the edge of its construction envelope.

remove :eaters +:

:egg:  +The term is no longer in common use.

:elbow:  This term may refer to a {signal elbow} or a {construction elbow}.  See also {elbow ladder}.

:elbow operation:  A {glider recipe} traveling on one or more {construction lane}s, that collides with an elbow constellation and performs one of the standard transformations on it -- push, pull, emit, construct, duplicate, or delete.  See {construction elbow}.

:elementary conduit:  A {conduit} with no recognizable active signal stage besides its input and output.  Theoretically an elementary conduit may become a composite conduit, if another conduit can be found that shares the beginning or end of the conduit in question.  In practice this happens very rarely, because many of the most likely branch points have already been identified:  standard spaceship, Herschel, B-heptomino, R-pentomino, pi, queen-bee shuttle, ...?

:envelope: {construction envelope}

:F116: One of the original sixteen {Herschel conduit}s, discovered by Paul Callahan in February 1997.  After 116 ticks, it produces a {Herschel} at (32, 1) relative to the input.  Its {recovery time} is 138 ticks; this can be reduced to 120 ticks by adding extra mechanisms to suppress the internal glider.  It is {Spartan} only if the following conduit is a {dependent conduit}, so that the {welded} {FNG} eater can be removed.  A {ghost Herschel} in the pattern below marks the output location:

   ........o..........................
   ........ooo........................
   ...........o.......................
   ..........oo.......................
   ...................................
   ...................................
   ...................................
   ...................................
   ...................................
   ...................................
   ...................................
   ...................................
   ...................................
   ...................................
   o..................................
   o.o.............................o..
   ooo.............................o..
   ..o.............................ooo
   ..................................o
   ...................................
   ...................................
   ...................................
   ...................................
   .........................oo........
   ...................oo.....o........
   ...................o.o.ooo.........
   ............oo.......o.o...........
   ............oo.......oo............

:F117: One of the original sixteen {Herschel conduit}s, discovered by Dave Buckingham in July 1996.  After 117 ticks, it produces a {Herschel} at (40, -6) relative to the input.  Its {recovery time} is 63 ticks.  It can be made {Spartan} by replacing the snake with a fishhook eater in one of two orientations.  A {ghost Herschel} in the pattern below marks the output location:

   ......................oo.....................
   .......................o.....................
   ..........o...........o......................
   ..........ooo.........oo.....................
   .............o...............................
   oo..........oo...............................
   .o...........................................
   .o.o.........................................
   ..oo.........................................
   .........................oo...............o..
   .........................oo...............o..
   ..........................................ooo
   ............................................o
   .............................................
   .............................................
   ..o..........................................
   ..o.o........................................
   ..ooo........................................
   ....o...........oo...........................
   ................o............................
   .................ooo.........................
   ...................o.........................

:F166: One of the original sixteen {Herschel conduit}s, discovered by Paul Callahan in May 1997.  Along with the {Lx200}, it is one of the two original {dependent conduits} (several more have since been discovered).  After 166 ticks, it produces a {Herschel} at (49, 3) relative to the input.  Its {recovery time} is 116 ticks.  A {ghost Herschel} in the pattern below marks the output location.  It can be made {Spartan} by replacing the snake with a fishhook eater in one of two orientations.  The input shown here is a Herschel great-grandparent, since the Herschel is catalysed by the {transparent} block before its standard form appears:

   .................................oo.....................
   ..................................o.....................
   .................................o......................
   .................................oo.....................
   ........................................................
   ........................................................
   .oo.....................................................
   ooo.oo..................................................
   .oo.ooo.oo..............................................
   ooo.oo..oo..........................oo...............o..
   oo..................................oo...............o..
   .....................................................ooo
   .......................................................o
   ........................................................
   ........................................................
   ........................................................
   ......oo................................................
   .....o.o......................................oo........
   .....o.........................................o........
   ....oo.........................oo...........ooo.........
   ...............................oo...........o...........
   ........................................................
   ........................................................
   .................oo.....................................
   ..................o.....................................
   ...............ooo......................................
   ...............o........................................
   ...........................oo...........................
   ...........................o............................
   ............................ooo.........................
   ..............................o.........................

:F171: The seventeenth {Herschel conduit}, discovered by Brice Due in August 2006 in a search using only {eaters} as {catalyst}s.  This was the first new Herschel conduit discovery since 1998.  After 171 ticks, it produces a {Herschel} at (29, -17) relative to the input.  Its {recovery time} is 227 ticks, slower than many of the original sixteen conduits because of the delayed destruction of a temporary blinker, though it is clearly {Spartan}.  A {ghost Herschel} in the pattern below marks the output location:

   ..........o......................
   ..........ooo....................
   .............o...................
   ............oo...................
   .....o...........................
   .....ooo.........................
   ........o........................
   .......oo........................
   .................................
   ..............................o..
   ....oo........................o..
   .....o........................ooo
   .....o.o........................o
   ......oo.........................
   .................................
   .................................
   o................................
   ooo..............................
   ...o.............................
   ..oo.............................
   .................................
   .................................
   .................................
   .................................
   .................................
   .................................
   .o...............................
   .o.o.............................
   .ooo.............................
   ...o.............................
   .................................
   ..........oo.....................
   ...........o.....................
   ........ooo......................
   ........o........................

:fd:  Abbreviation for {full diagonals}.

:first natural glider:  The glider produced at T=21 during the evolution of a {Herschel}.  This is the most common signal output from a {Herschel conduit}.

:FNG:  See {first natural glider}.

:freeze-dried salvo: A constellaton of constructible objects which, when {trigger}ed by a single glider, produces a unidirectional glider {salvo}, and nothing else.  Freeze-dried salvos can be useful in {slow salvo} constructions, especially when an active circuit has to destroy or reconstruct itself.  The freeze-dried form can be considered to be a single-glider {seed} for the target salvo.

:French kiss: +For many years this was one of the best-known small oscillators with no known {glider synthesis}.  In October 2013 Martin Grant completed a 23-glider construction.

:frozen:  See {freeze-dried salvo}.

:full diagonals:  Diagonal measurement appropriate whenever an adjustable mechanism is present

:Fx119:  One of the original sixteen {Herschel conduit}s, discovered by Dave Buckingham in September 1996.  After 119 ticks, it produces an inverted {Herschel} at (20, 14) relative to the input.  Its recovery time is 231 ticks; this can be reduced somewhat by suppressing the output Herschel’s glider, or by adding extra {catalysts} to make the reaction settle more quickly. A {ghost Herschel} in the pattern below marks the output location:

   o......................
   o.o....................
   ooo....................
   ..o....................
   .......................
   .......................
   .......................
   .......................
   .......................
   .......................
   .......................
   .......................
   .......................
   .......................
   .......................
   .........oo...........o
   ....oo...oo.........ooo
   ....oo..............o..
   ....................o..
   .......................
   ...oo..................
   ....o....oo............
   .ooo.....oo............
   .o.....................

:Fx119 inserter:  A Herschel-to-glider converter and {edge shooter} based on an {Fx119}  Herschel conduit:

   .........o....................
   .........o.o..................
   .........ooo..................
   ...........o..................
   ..............................
   ..............................
   ..............................
   ..............................
   ..oo......oo..................
   ...o.......o..................
   ooo.....ooo...................
   o.......o.....................
   ..............................
   ..............................
   ..............................
   ..................oo..........
   .............oo...oo..........
   .............oo...............
   ..............................
   ..............................
   ............oo............oo..
   .............o....oo......o...
   ..........ooo.....oo.......ooo
   ..........o..................o

:Fx77: One of the original sixteen {Herschel conduit}s, discovered by Dave Buckingham in August 1996.  After 77 ticks, it produces an inverted {Herschel} at (25, -8) relative to the input.  Its {recovery time} is 61 ticks; this can be reduced slightly by suppressing the output Herschel’s glider, as in the {L112} case.  A {pipsquirter} can replace the blinker-suppressing eater to produce an extra glider output.  It is one of the simplest known {Spartan} conduits, and one of the few {elementary conduits} in the original set of sixteen.  A {ghost Herschel} in the pattern below marks the output location:

   o............................
   ooo..........................
   ...o.........................
   ..oo...........oo...........o
   ...............oo.........ooo
   ..........................o..
   ..........................o..
   .............................
   .............................
   .............................
   .o...........................
   .o.o.........................
   .ooo.........................
   ...o.........................
   .............................
   .............................
   .............................
   .............................
   .............................
   ................oo...........
   ................o.o..........
   ..................o..........
   ..................oo.........

:Fx153: One of the original sixteen {Herschel conduit}s, discovered by Paul Callahan in February 1997.  After 153 ticks, it produces an inverted {Herschel} at (48, -4) relative to the input.  Its {recovery time} is 69 ticks.  It can be made {Spartan} by replacing the snake with a fishhook eater in one of two orientations.  A {ghost Herschel} in the pattern below marks the output location:

:Fx158: One of the original sixteen {Herschel conduit}s, discovered by Dave Buckingham in July 1996.  After 158 ticks, it produces an inverted {Herschel} at (27, -5) relative to the input.  Its {recovery time} is 176 ticks.  It is the only known conduit that does not produce its output Herschel via the usual great-grandparent, so it cannot be followed by a {dependent conduit}.  A {ghost Herschel} in the pattern below marks the output location:

:Fx176: One of the original sixteen {Herschel conduit}s, discovered by Paul Callahan in October 1997.  After 176 ticks, it produces an inverted {Herschel} at (45, 0) relative to the input.  Its {recovery time} is 92 ticks.  A {ghost Herschel} in the pattern below marks the output location:

   ..............................oo..................
   ..............................oo..................
   ..................................................
   .................oo...............................
   ..................o...............................
   ..................o.o.............................
   ...................oo.............................
   ..................................................
   ..................................................
   ..............oo..................................
   ......o.......oo..................................
   ......ooo.........................................
   .........o........................................
   ........oo........................................
   ..................................................
   oo................................................
   .o................................................
   .o.o.....................................oo.......
   ..oo......................................o.......
   ..........................................o.o.....
   ...........................................o.o....
   ............................................o...oo
   ................................................oo
   ..................................................
   ..................................................
   ..o...............................................
   ..o.o...............................oo...........o
   ..ooo...............................oo.........ooo
   ....o..........................................o..
   ...............................................o..
   ..............oo........oo........................
   ..............oo..oo.....o........................
   ..................o.o.ooo.........................
   ....................o.o...........................
   ....................oo....oo......................
   .........................o.o....oo................
   .........................o......oo................
   ........................oo........................

:Game of Life News:  A blog reporting on new Life discoveries, started by Heinrich Koenig in December 2004, currently found at http://pentadecathlon.com/lifenews/.
+[Maybe write to Koenig, see if he's planning to shut that link down any time soon...]

:Garden of Eden: +The following shows a 10x10 Garden of Eden found by Marijn Heule, Christiaan Hartman, Kees Kwekkeboom, and Alain Noels in 2013 using SAT-solver techniques.  An exhaustive search of 90-degree rotationally symmetric 10x10 patterns was possible because the symmetry reduces the number of unknown cells by a factor of four.

   .o.ooo.o..
   ..o.o.o..o
   o.ooo..oo.
   .o.ooooo.o
   o..o..oooo
   oooo..o..o
   o.ooooo.o.
   .oo..ooo.o
   o..o.o.o..
   ..o.ooo.o.

:Gemini: The first {self-constructing} spaceship, and also the first {oblique} spaceship, traveling at a speed of (5120,1024)c/33699586.  It was made public by Andrew Wade on 18 May 2010.  It was the thirteenth explicitly constructed spaceship velocity in Life, and made possible an infinite family of related velocities.  The Gemini spaceship derives its name from the Latin “gemini”, meaning twins, describing its two identical halves, each of which contains three Chapman-Greene {construction arms}. A tape of gliders continually relays between the two halves, instructing each to delete its parent and construct a daughter configuration.

:Geminoid:  TBD

:ghost Herschel:  A {dying spark} made by removing one cell from the {Herschel} heptomino.  This particular spark has the advantage that, when placed in a conduit to mark the location of an input or output Herschel, it disappears cleanly without damaging adjacent catalysts, even in {dependent conduit}s.

   o..
   o..
   ooo
   ..o

:Golly:  +does anything need adding?  Multistate rules, unbounded and bounded grids, etc? Seems pretty good the way it is, really.

:Gotts dots: A 41-cell 187×39 {superlinear growth} pattern, O(t ln(t)), found by Bill Gosper in March 2006.  Collisions within the pattern cause it to sprout its Nth {switch engine} at generation T = ~224n-6.

:half-bakery reaction:  the key reaction used in the {half-baked knightship} and {parallel HBK}, where a half-bakery is moved by (6,3) when a glider collides with it, and the glider continues on a new lane.  Pairs of these reactions at the correct relative spacing can create 90-degree output gliders:

     ....
     ....
     ....
     ....TBD
x = 31, y = 25, rule = B3/S23
29bo$28bo$28b3o8$20b2o$19bo2bo$19bobo$17b2obo$8bo7bo2bo$6b2o8bobo$7b2o
8bo2$4b2o$3bo2bo$3bobo$b2obo$o2bo$obo$bo!

:half-baked knightship:  TBD

:half-diagonals:  TBD

:Halfmax:   A pattern that acts as a spacefiller in half of the Life plane, found by Jason Summers in May 2005. It expands in three directions at c/2, producing a triangular region that grows to fill half the plane.

:hashlife: -It is not, however, suitable for showing a continuous display of the evolution of a pattern.  Add mention of {Golly}.

:H-to-G: A {Hershel-to-glider} converter.

:HBK:  {half-baked knightship}

:hd:  Abbreviation for {half-diagonals}.

:hand:  Any object used as a {slow salvo} {target} by a {construction arm}.

:helix:  +Give speed for the example helix.

:Herschel:  +Herschels are one of the most versatile types of {signal} in stable circuitry.  {R-pentomino}es and {B-heptomino}es naturally evolve into Herschels, and {converters} have also been found that change {pi heptomino}es and several other signal types into Herschels, and vice versa.  See {elementary conduit}.

:Herschel receiver:  +Any {circuit} that converts two incoming gliders on parallel {lanes} into a Herschel signal.  The following diagram shows a...

:Herschel climber: The following glider-supported reaction, which can be repeated every 79 ticks, moving the Herschel 23 cells to the right and 5 cells upward, and releasing two gliders to the northwest and southwest:
    ...TBD
x = 36, y = 16, rule = B3/S23
15bobo15bo$15b2o15bobo$16bo15bo2bo$33b2o9$o$obo$3o$2bo!

As the diagram shows, it is possible to substitute a loaf or other still lifes for some or all of the support gliders.  This fact is used to advantage at the front end of the {waterbear} spaceship.

:Herschel conduit:  -Sixteen simple stable Herschel conduits are currently known, having been discovered from 1995 onwards by Dave Buckingham (DJB) and Paul Callahan (PBC).
+More than fifty simple stable Herschel conduits are currently known.  The exact number depends on the definition of "simple".  In general a Herschel conduit can be called "simple" if its active reaction does not return to a  Herschel stage except at its output.  Compare {elementary conduit}, {composite conduit}.

The original {universal} set consisted of sixteen stable Herschel conduits, discovered between 1995 and 1998 by Dave Buckingham (DJB) and Paul Callahan (PBC).

{R64}    R   -11   9   DJB, Sep 1995
{Fx77}   Ff   -25   -8   DJB, Aug 1996
{L112}   L   -12  -33   DJB, Jul 1996
{F116}   F   -32   1   PBC, Feb 1997
{F117}   F   -40   -6   DJB, Jul 1996
{Bx125}   Bf    9  -17   PBC, Nov 1998
{Fx119}   Ff   -20   14   DJB, Sep 1996
{Fx153}   Ff   -48   -4   PBC, Feb 1997
{L156}   L   -17  -41   DJB, Aug 1996
{Fx158}   Ff   -27   -5   DJB, Jul 1996
{F166}   F   -49   3   PBC, May 1997
{Fx176}   Ff   -45   0   PBC, Oct 1997
{R190}   R   -24   16   DJB, Jul 1996
{Lx200}   Lf   -17  -40   PBC, Jun 1997
{Rx202}   Rf   -7   32   DJB, May 1997
{Bx222}   Bf    6  -16   PBC, Oct 1998

TBD: Break down each composite Herschel conduit of the original set of sixteen:  e.g., L156 = HLx69R + RF28B + {B59H}.  Won't take much more space.  Not going to define HLx69R or any of the hundred-and-umpteen other named elementary conduits, just B59H as a prime example of the breed (the LifeWiki has it as “Conduit 1”, and it was already in the Life Lexicon as “probably the most remarkable conduit”.)

:Herschel-to-glider converter: The largest category of {elementary conduit}.  Gliders are very common and self-supporting, so it’s much easier to find these than any other type of output {signal}.  A large collection of H-to-G converters has been compiled, with many different output {lane}s and timings.  These can be used to synchronize multiple signals to produce {gun} patterns or complex logic circuitry.  See {NW31T120} for an example.

:Herschel-pair climber:  The mechanism defining the rate of travel of the {Centipede} and {shield bug} spaceships.  Compare {pi climber}.  It consists of a pair of {Herschels} climbing two parallel chains of blocks.  Certain spacings between the block chains allow gliders from each Herschel to delete the extra ash objects produced by the other Herschel.  Another glider escapes to each side, leaving only an exact copy of the original block chains, but shifted forward by 9 cells:

   oo.........................................................oo
   oo.........................................................oo
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   oo.........................................................oo
   oo.........................................................oo
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .......................................................ooo...
   .......................................................o..o..
   .......................................................o..o..
   ......................................................oooo...
   .......ooo............................................oo.....
   ........o............................................o.......
   ......ooo.............................................o......
   ......................................................o......

:highway robber: any mechanism that can retrieve a signal from a spaceship {lane} while allowing spaceships on nearby lanes to pass by unaffected.  In practice the spaceship is generally a glider.  The signal is removed from the lane, an output signal is generated elsewhere, and the highway robber returns to its original state.  A competent highway robber does not affect gliders even on the lane adjacent to the affected glider stream, except during its recovery period.

A perfect highway robber doesn’t affect later gliders even in the lane to which it is attached, even during its recovery period.  Below is a near-perfect highway robber “bait” that requires three synchronized signals to rebuild (the {Herschel}, {B-heptomino}, and {glider}.)  The glider at the top right passes by unharmed, but another glider following on the same {lane} 200 ticks later will be cleanly reflected to a new path -- and another glider following that one will also pass by unharmed.  The only imperfection is a few ticks at the very end of the reconstruction, as the beehive is being rebuilt::

   ......................o...........o.........
   ......................ooo.......o.o.........
   .........oo...oo.........o.......oo.........
   .........oo...oo........oo..................
   ............................................
   ............................................
   ..oo........................................
   ...o........................................
   ...o.o......................................
   ....oo......................................
   ............................................
   ............................................
   ............................................
   ............................................
   ............................................
   ............................................
   .......oo...................................
   ........o...................................
   .....ooo....................................
   .....o......................................
   ............................................
   ............................................
   ............................................
   ............................................
   ............................................
   ............................................
   ....................oo......................
   ....................oo......................
   ............oo..............................
   .............o..............................
   o.........ooo...............................
   ooo.......o.................................
   ...o........................................
   ..oo........................................
   ............................................
   ............................................
   ............................................
   ............................................
   ...........o...........oo...............oo..
   .........ooo..........o.o...............oo..
   .........o.o............o...................
   .........o.....................oo.o.......o.
   ...............................o.oo......ooo
   ........................................oo.o
   ............................................
   .............................oo.............
   .............................oo.............
   .......................oo...................
   .......................oo...................
   ............................................
   ............................................
   .........................oo.................
   ..................oo.....oo.................
   ..................oo........................

:HW volcano: +At least four progressively smaller forms of this sparker have been found, including a 25-cell-wide version found by David Eppstein in 2003, and a vertically narrower 28-cell-wide version by Karel Suhajda in 2004.  Scot Ellison’s 17-cell-wide version is shown in the {zweiback} entry.

Have a look through it, if you have a moment. I'm offering a bounty of 256 gliders to anyone who finds an error.

I through Z will be along shortly.
dvgrn
Moderator
 
Posts: 3991
Joined: May 17th, 2009, 11:00 pm
Location: Madison, WI

Re: Life Lexicon update

Postby dvgrn » February 10th, 2016, 11:03 pm

I through Z additions to current 2006 Lexicon. There may be some duplication with the 2007 draft I posted at the beginning of this thread, come to think of it -- I'll have to go back and double-check those, as a next step. Anyway:

:independent conduit:  A {Herschel conduit} in which the input Herschel produces its {first natural glider}.  Compare {dependent conduit}.

:infinite growth: +add link to {quadratic growth}

:intermediate target:  A temporary product of a partial {slow salvo}, {elbow operation}, or {glider synthesis}.  An intermediate target is a useful step toward a desired outcome, but will not appear in the final construction.

:kickback: +Another two-glider collision also produces a 180-degree output glider.  This can also be referred to as a kickback reaction, though it is used less often in constructions because the gliders come from opposite directions:

   .o.
   o..
   ooo
   ...
   ...
   .oo
   o.o
   ..o

:knightship: +The first Conway's Life knightship was a variant of Andrew Wade's Gemini spaceship, constructed in May 2010.  The next was an even slower knightship based on the {half-bakery reaction}.

:L112: One of the original sixteen {Herschel conduit}s, discovered by Dave Buckingham in July 1996.  After 112 ticks, it produces a {Herschel} turned 90 degrees counterclockwise at (12, -33) relative to the input.  Its {recovery time} is 61 ticks; this can be reduced slightly by removing the output glider, either with a specialized eater (as in the original {true} p59 gun), or with a {sparker} as in most of the {Quetzal} guns.  It can be made {Spartan} by replacing the {aircraft carrier} with a fishhook eater in one of two orientations.  A {ghost Herschel} in the pattern below marks the output location:

   ...............oo.......
   ...............o........
   .............ooo........
   ........................
   ........................
   ........................
   ........................
   ........................
   ........................
   ........................
   ........................
   ........................
   ........................
   ........................
   ........................
   ........................
   ........................
   ........................
   .............oo.........
   .............oo.........
   ....oo..................
   ....o..o................
   oo....oo................
   .o....................oo
   .o.o..................o.
   ..oo................o.o.
   ....................oo..
   ........................
   ........................
   ........................
   ........................
   ........................
   ..o.....................
   ..o.o...................
   ..ooo...................
   ....o...................
   ........................
   ..............oo........
   ..............oo..oo....
   ..................o.o...
   ....................o...
   ....................oo..

:L156: One of the original sixteen {Herschel conduit}s, discovered by Dave Buckingham in August 1996.  After 156 ticks, it produces a {Herschel} turned 90 degrees counterclockwise at (17, -41) relative to the input.  Its {recovery time} is 62 ticks.  It can be made {Spartan} by replacing the snake with a fishhook eater in one of two orientations.  A {ghost Herschel} in the pattern below marks the output location:

   ...................oo........
   ...................o.........
   .................ooo.........
   .............................
   .............................
   .............................
   .............................
   .............................
   .............................
   .............................
   .............................
   .............................
   .............................
   .............................
   .............................
   .............................
   .............................
   .............................
   .................oo..........
   .................oo..........
   .............................
   ........oo.o.................
   ........o.oo.................
   ..........................oo.
   ..........................o..
   ........................o.o..
   ........................oo...
   .............................
   .........o...................
   .........ooo.................
   o...........o................
   ooo........oo..............o.
   ...o......................o.o
   ..oo.......................o.
   .............................
   .............................
   .............................
   .............................
   .............................
   .............................
   .o....................oo.....
   .o.o..................o.o....
   .ooo....................o....
   ...o...........oo.......oo...
   ...............o.............
   ................ooo..........
   ..................o..........

:lane:  a path traveled by a glider, or less commonly, a spaceship such as a loafer.  The lane is centered on the line of symmetry (if any) of the spaceship in question.  If a lane is clear, then the spaceship can travel along it without colliding or interfering with any other objects.

Diagonal lanes are often numbered consecutively, in half-diagonals ({hd}).  Occasionally diagonal lane measurements are given in quarter-diagonals ({qd}), in part because diagonally symmetric spaceships have a line of symmetry 1qd away from the lines available for gliders.  It’s also convenient that moving a glider forward by 100qd (for example) has the same effect as evolving the same glider for 100 ticks.

:LifeHistory:  A multistate CA rule equivalent to two-state B3/S23 Life, but with several additional states intended for annotation purposes.  A “history” state records whether an off cell has ever turned on in the past, and other states allow on and off cells to be permanently or temporarily marked, without affecting the evolution of the pattern.

:lifesrc:  +A Java version, JavaLifeSearch, was written in November 2012 by Karel Suhajda.

:LifeViewer:  A scriptable Javascript Life pattern viewer written by Chris Rowett, used primarily on the conwaylife.com discussion forums.

:lightspeed wire: +TBD: Add Jason Summers' discovery of beehive lightspeed wire in October 2002.

:linear propagator: a self-replicating pattern in which each copy of a pattern produces one child that is an exact copy of itself.  The child pattern then blocks the parent from any further replication.   An example was constructed by Dave Greene on 23 November 2013.  By some definitions, due to its limited one-dimensional growth pattern, the linear propagator is not a true replicator, Compare {quadratic replicator}.

:loafer: a c/7 spaceship discovered by Josh Ball on 17 February 2013:

   .oo..o.oo
   o..o..oo.
   .o.o.....
   ..o......
   ........o
   ......ooo
   .....o...
   ......o..
   .......oo

It has a known 8-glider construction {recipe}, probably not minimal, discovered on the following day:

   .................................o
   ...............................oo.
   ................................oo
   .........o........................
   .o........o.......................
   ..o.....ooo.......................
   ooo...............................
   ..................................
   ..................................
   .....o............................
   ......o...........................
   ....ooo...........................
   ........................o.o.......
   .........................oo.......
   .........................o........
   ..................................
   ...........................o.o....
   ...........................oo.....
   ............................o.....
   ...............................ooo
   ...............................o..
   ................................o.
   ..................................
   ..................................
   ..................................
   ..................................
   ..................................
   ..................................
   .....oo...........................
   ......oo..........................
   .....o............................

The loafer was therefore the first new glider-constructible spaceship in almost a decade.  (A glider synthesis for a 2c/5 ship, 60P5H2V0, was found in March 2003.)

:Lx200: One of the original sixteen {Herschel conduit}s, discovered by Paul Callahan in June 1997.  Along with the {F166}, one of the two original {dependent conduits} (several more have since been discovered.)  After 200 ticks, it produces an inverted {Herschel} turned 90 degrees counterclockwise at (17, -40) relative to the input.  Its {recovery time} is 90 ticks.  It can be made {Spartan} by replacing the snakes with fishhook eaters in one of two orientations. A {ghost Herschel} in the pattern below marks the output location. The input shown here is a Herschel great-grandparent, since the Herschel is catalysed by the {transparent} block before its standard form appears:

   .....................oo.............
   ......................o.............
   ......................ooo...........
   ....................................
   ....................................
   ....................................
   ....................................
   ....................................
   ....................................
   ....................................
   ....................................
   ....................................
   ....................................
   ....................................
   ....................................
   ....................................
   ....................................
   ....................................
   .......................oo...........
   .......................oo...........
   ....................................
   ..............................o.oo..
   ..............................oo.o..
   ....................................
   ....................................
   ..............o.oo..................
   ..............oo.o..................
   ....................................
   ....................................
   ....................................
   ....................................
   ....................................
   ....................................
   ....................................
   ....................................
   ....................................
   ....................................
   ................................oo..
   ................................o.o.
   .oo...............................o.
   ooo.oo............................oo
   .oo.ooo.oo..........................
   ooo.oo..oo..........................
   oo..................................
   ....................................
   ....................................
   ....................................
   ................................oo..
   ................................oo..
   ....................................
   ......oo............................
   .......o............................
   ....ooo.........................oo..
   ....o...........................oo..
   ..................oo................
   .................o.o................
   .................o..................
   ................oo........oo........
   ..........................o.........
   ...........................ooo......
   .............................o......

:macro-spaceship: a {self-constructing} or {self-supporting} spaceship, such as the {Caterpillar}, {Centipede}, {half-baked knightship}, {waterbear}, and {Demonoid}.  Engineered spaceships of these types are inevitably large and complex.

:metacatacryst:  -This is currently the smallest known pattern (in terms of initial population) with superlinear growth.  +It was the smallest known pattern with superlinear growth, until the discovery (also by Gotts) of {26-cell quadratic growth}.

:metapixel:  See {OTCA Metapixel}.

:monochromatic salvo:  A {slow salvo} that uses gliders of only one {colour}.  For example, the slow salvos generated by {half-baked knightship}s are monochromatic, because they’re generated by a single type of reaction which can happen at any position along a diagonal line.  The smallest step is one {full diagonal} (1fd), which is two {half diagonal}s (2fd), so the glider-producing reaction can only reach half of the available lanes.

:monoparity salvo:   A {slow salvo} that uses gliders of only one {parity}.  Compare {monochromatic salvo}.

:NW31:  One of the most common stable {edge-shooter}s.  This Herschel-to-glider {converter} suppresses the junk ordinarily left behind by an evolving {Herschel} while allowing both the {first natural glider} and {second natural glider} to escape on {transparent lane}s:

   .......oo.......................
   ........o.......................
   ........o.o.....................
   .........oo.....................
   ................................
   ................................
   ................................
   ..............................oo
   ..............................oo
   ................................
   .........o......................
   .........o.o....................
   .........ooo....................
   ...........o....................
   ................................
   ................................
   ................................
   ................................
   ..oo............................
   ...o............................
   ooo.............................
   o...............................
   ....................oo..........
   ....................oo..........

:NW31T120: The full designator of {NW31}. The T120 timing measurement means that a canonical NW glider placed at time T=120, at (+31, +0) relative to the input Herschel, would reach the exact same spacetime locations as the converter's output glider (assuming no interference from the conversion circuitry).

:nonfiller: See {space nonfiller}

:omniperiodic:  TBD  +most recent list of remaining periods = ;-recent discoveries no longer all found by Noam Elkies.

:one per generation:  See {grow-by-one object}.

:orphan:  -- TBD: distinguish from GoE according to modern usage:  TBD.  Is it something like, a GoE is the entire plane, where an orphan is just the ON and OFF cells needed to ensure no parent is possible?

:OTCA Metapixel: A 2048 × 2048 period 35328 {unit cell} constructed by Brice Due in 2006.  It contains a large “pixel” area that contains a large population of {LWSS} spaceships when the cell state is ON, but is empty when the cell state is OFF.  This allows the state of the cell to be visible at high zoom levels, unlike all previous unit cells where the state was signaled by the presence or absence of a single glider in a specific location.

:overclocking:  A term used in {staged-recovery circuit}s.  TBD

:parity: Even or odd, particularly as applied to the {phase} of an oscillator or spaceship.  For example, in {slow salvo} constructions, the {intermediate target}s are frequently period 2 -- most often they contain {blinker}s or {traffic light}s.  A glider striking a P2 constellation will generally produce a different result depending on its parity.  Conversely, it doesn’t matter if an incoming glider is in phase 1 or phase 3, because period-4 intermediate targets are rare (or not used).  TBD...

:single-arm:  A type of {universal constructor} using just one construction arm and {slow-salvo} techniques to construct, usually, {Spartan} or near-Spartan circuitry.  Compare {two-arm}.
:shoulder: The fixed upper end of a {construction arm}, generally consisting of one or more glider {gun}s or {edge shooter}s aimed at an {elbow} object.

:target:  TBD

:two-arm:  TBD.  Original {Gemini} example.

:p5 reflector:  TBD

:p6 pipsquirter:  TBD

:p6 reflector:  TBD

:p7 pipsquirter:  TBD

:p7 reflector:  TBD

:p8 reflector:  TBD

:p8 G-to-H:  TBD

:parallel HBK:  A much smaller successor to the {half-baked knightship}, constructed by Chris Cain in September 2014.  Several slow-salvo recipes are needed to support the multi-glider salvo {seed}s at the upstream end of the spaceship.  "Parallel" means that these recipes are sent in parallel instead of one after the other, in series, as in the original HBK.


:parasite: A self-sustaining reaction attached to the output of a rake or puffer, that damages or modifies the standard output.  Compare {tagalong}.  In 2009, while experimenting with {novelty generating} patterns in {Golly}, Mitchell Riley discovered parasites on glider streams from p20 and p8 backward rakes.  In some cases, parasites can even “reproduce”, as in the pattern below, though the number of copies is limited since they will eventually use up their host glider stream:

   ......o.............o.........
   .....ooo...........ooo........
   ...oo.ooo.........ooo.oo......
   ....o..o.oo.....oo.o..o.......
   .oo.o....o.o...o.o....o.oo....
   .oo.o.o..o.oo.oo.o..o.o.oo....
   .o........o.o.o.o........o....
   oo.......oo.o.o.oo.......oo...
   ............o.o...............
   .......ooo.o...o.ooo..........
   ......oo...........oo.........
   ......o.....o....oo..o........
   .....oo....ooo...oo..o........
   ...........o.oo...ooo.........
   ............ooo....o..........
   ............ooo...............
   ............ooo...............
   ............oo................
   ..............................
   ...................o.o........
   ....................oo........
   ...............oo...o.........
   ........oo......oo............
   .......oo......o..............
   .........o....................
   ..............................
   ..............................
   .................oo...........
   ..........o......ooo..........
   .........ooo.o...ooo..........
   ........oo.o.....ooo..........
   ........oo......o.oo..........
   ........oo......ooo....oo.....
   ........oo.oo....o.....o......
   .........oo...........oo......
   ..........ooo.o...o.ooo.......
   ...............o.o............
   ...oo.......oo.o.o.oo.......oo
   ....o........o.o.o.o........o.
   ....oo.o.o..o.oo.oo.o..o.o.oo.
   ....oo.o....o.o...o.o....o.oo.
   .......o..o.oo.....oo.o..o....
   ......oo.ooo.........ooo.oo...
   ........ooo...........ooo.....
   .........o.............o......

:period multiplier:  A commonly used term for a {pulse divider}.  Dividing the number of {signal}s in a regular stream by N necessarily multiplies the {period} by N.  For Herschel signals, a number of small period doubler, tripler, and quadrupler mechanisms are known.  The term "period multiplier" can be somewhat misleading, because most such circuits can accept aperiodic input streams.

:pi climber:  The reaction that defines rate of travel of the {Caterpillar} spaceship.  A pi climber consists of a pi-heptomino “climbing” a chain of blinkers, moving 17 cells every 45 ticks, and leaving behind an identical chain of blinkers, shifted downward by 6 cells.  A single pi climber does not produce any gliders or other output, but two or more of them traveling on nearby blinker chains can be arranged to emit gliders every 45 ticks.  Compare {Herschel-pair climber}.
   ..o..
   ..o..
   ..o..
   .....
   .....
   .....
   .....
   .....
   .....
   .....
   .....
   .....
   .....
   .....
   .....
   ..o..
   .ooo.
   .o.o.

:pulse divider: +For n=2, the simplest known stable pulse divider is the {semi-Snark}.

:quadratic replicator:  A pattern that fills all or part of the Life plane by making copies of itself in a nonlinear way.  Small quadratic replicators are known in other Life-like rules, but no example has been found or constructed in Conway’s Life as of January 2016.

:quadratic growth: The fastest possible rate of population growth for a finite Life pattern -- O(t^2) in big-O notation, where t is the number of ticks.  See {superlinear growth}.

:quarter:  +the name is due to the minimum population of 25 cells.

:qd:  Abbreviation for {quarter-diagonals}.

:quadratic sawtooth:  TBD

:quarter-diagonals:  TBD

:R64: One of the original sixteen {Herschel conduit}s, discovered by Dave Buckingham in September 1995; also one of two known {Blockic} Herschel conduits.  After 64 ticks, it produces a {Herschel} rotated 90 degrees clockwise at (11, 9) relative to the input.  Its {recovery time} is 153 ticks, though this can be improved to 61 ticks by adding a from-the-side eater inside the turn to avoid interference from the output Herschel’s {first natural glider}, as shown below.  It is one of the simplest known {Spartan} conduits, one of the two known {Blockic} conduits, and one of the few {elementary conduits} in the original set of sixteen. A {ghost Herschel} in the pattern below marks the output location:

   ..........oo...........
   ..........oo.....oo....
   .................oo....
   .......................
   .......................
   ...............oo......
   ...............oo......
   .....................oo
   .....................oo
   .......................
   .......................
   .......................
   .o.....................
   .o.o...................
   .ooo...................
   ...o...................
   .......................
   .......................
   .......................
   ...oo.oo...............
   ..o.o.o.o..............
   ..o.o..o...............
   .oo.o........ooo.......
   o...oo.......o.........
   .o.o..o.o...oo.........
   oo.oo..oo..............

:recovery time:  The number of {ticks} that must elapse after a {signal} is sent through a {conduit}, before another signal can be safely sent on the same path.  In general, a lower recovery time means a more useful conduit.  For example, the {Snark}'s very low recovery time allowed for the creation of {oscillator}s with previously unknown {period}s, 43 and 53.

:rectifier:  Smallest and fastest known stable 180-degree reflector, with a repeat time of 106.  Was the smallest stable reflector until the discovery of the {Snark} in 2013.

-- :receiver:, :transceiver:, :transmitter:   change "path" to "lane" and "tracks" to "lanes"

:rectifier: A 180-degree {reflector} discovered by Adam P. Goucher in 2009.  It has the same output glider as the {boojum reflector} but a much shorter {repeat time} of only 106 ticks.  Another advantage of the rectifier is that the output glider is on a {transparent lane}, so it can be used in logic circuitry to merge two signal paths.

   ..o.........................................
   o.o.........................................
   .oo.........................................
   ............................................
   ..............o.............................
   .............o.o............................
   .............o.o............................
   ..............o.............................
   ............................................
   ............................................
   ............................................
   ............................................
   ............................................
   ............................................
   ............................................
   ............................................
   ............................................
   ............................................
   ............................................
   .......................oo...................
   .......................oo...................
   ............................................
   .....oo.....................................
   ....o.o.....................................
   ....o.......................................
   ...oo.......................................
   ..................................oo........
   .................................o..o..oo...
   .................................o.o....o...
   ..............oo..................o.....o.oo
   .............o.o.....................oo.o.o.
   .............o.......................o..o..o
   ............oo....................o....o..oo
   ..................................ooooo.....
   ............................................
   ....................................oo.o....
   ....................................o.oo....
   ............................ooo.............
   ............................o...............
   .............................o..............

:reflector: - simplify early-history text, add {rectifier} and {Snark}, remove my prize offer (won by Mike Playle) and add Mike’s prizes.

:replicator: +add note about {linear propagator}.

:rle: +is now the usual means of exchanging Life patterns by e-mail or in online forum discussions.

:R190: One of the original sixteen {Herschel conduit}s, discovered by Dave Buckingham in July 1996.  After 190 ticks, it produces a {Herschel} turned 90 degrees clockwise at (24, 16) relative to the input.  Its {recovery time} is 107 ticks.  A {ghost Herschel} in the pattern below marks the output location:

   ..........oo.........................
   .......oo..o.........................
   .....ooo.oo..........................
   ....o................................
   .o..oooo.oo..........................
   .ooo...o.oo..........................
   ....o................................
   ...oo..........................oo....
   ...............................o.....
   .............................o.o.....
   .............................oo......
   .....................................
   .....................................
   .....................................
   .....................................
   .................................oo.o
   .................................o.oo
   .....................................
   o.........................oo.........
   o.o.......................oo.........
   ooo..................................
   ..o..................................
   .....................................
   .....................................
   .........oo...oo.....................
   ..........o...o......................
   .......ooo.....ooo...................
   .......o.........o...................
   .................o.o.................
   ..................oo.................
   .....................................
   .....................................
   .....................................
   .....................................
   .....................................
   .........................ooo.........
   .........................o...........
   ........................oo...........

:Rx202: One of the original sixteen {Herschel conduit}s, discovered by Dave Buckingham in May 1997.  After 202 ticks, it produces an inverted {Herschel} turned 90 degrees clockwise at (7, 32) relative to the input.  Its {recovery time} is 201 ticks.  A {ghost Herschel} in the pattern below marks the output location:

   ..............oo...............
   ...........oo..o...............
   .........ooo.oo......o.........
   ........o..........ooo.........
   .........ooo.oo...o............
   ...........o.oo...oo...........
   ...............................
   ...............................
   ...............................
   ...............................
   .......................oo......
   .......................o.......
   .....................o.o.......
   .....................oo........
   ...............................
   ...............................
   ...............................
   ...............................
   ...............................
   ...o...........................
   ...o.o.........................
   ...ooo.........................
   .....o.........................
   ......................oo.......
   ......................oo.......
   ...............................
   ...............................
   ...............................
   ...............................
   ...............................
   ...............................
   ...............................
   o.oo...........................
   oo.o...........................
   .....................oo........
   .........oo.........o..o..oo...
   .........oo.........o.o....o...
   .....................o.....o.oo
   ........................oo.o.o.
   ........................o..o..o
   .....................o....o..oo
   .....................ooooo.....
   ...............................
   ...................ooooooo.....
   ...................o..o..o.....
   .................o.o...........
   .................oo............
   ...............................
   ...............................
   ...............................
   ...............................
   ...............................
   .........ooo...................
   ...........o...................
   ...........oo..................

:sawtooth: +info about Sawtooth 177.

:semi-Snark:  The following period-doubling circuit, which absorbs every other input glider and reflects the remaining gliders by 90 degrees.  Found by Sergey Petrov in 2013:

   ......o..........oo
   .......oo........o.
   ......oo.......o.o.
   ...............oo..
   ..........o........
   oo.........oo......
   oo........oo.......
   ...................
   ...................
   .................oo
   ..........oo.....oo
   ..........oo.......
   ...................
   .....o.............
   ....o.o............
   ....oo......oo.....
   ............o......
   .............ooo...
   ...............o...

:SGR: +This term is no longer in use.

:SNG:  {second natural glider}.

:second natural glider:  The glider produced at T=72 during the evolution of a {Herschel}.  This is the common edge-shooting glider output used in the {NW31} converter and several other converter variants.

:signal: +Signals are used in Herschel circuitry, universal constructors, macro-spaceships...

:single-lane construction:  TBD

:switch:  TBD.  [Use the dependent-conduit ON/OFF switch as an example? What’s smaller?]

:switchable gun:  A {gun} that includes a mechanism to turn the output stream off and on with a simple signal, often a glider.  A small example is Dietrich Leithner’s switchable LWSS gun from July 8, 1995.  The ON signal enters from the northeast, and the OFF signal from the northwest:

   .................oo...........................................
   .................o..o.........................................
   ..............................................................
   .....................o........................................
   ..............................................................
   .o.................oo.........................................
   ..o...............o...........................................
   ooo...........................................................
   ..............................................................
   ...............oo...oo........................................
   ...............oo...oo........................................
   ................ooooo........................o................
   .................o.o........................o.................
   ............................................ooo...............
   .................ooo..........................................
   ....................................o.o.......................
   ....................................o...o.....................
   ........................................o.......o.............
   ..........................oo........o....o....oooo............
   ..........................oo............o....o.o.oo...........
   .....................o..............o...o...o..o.ooo........oo
   ......................o.............o.o......o.o.oo.........oo
   ....................ooo.......................oooo............
   ................o...............................o.............
   ...............ooo...................o........................
   ..............ooooo..................o.o.....o................
   .............oo...oo.................oo....ooo................
   ..........................................o...................
   .............................o............oo..................
   ...........................o..o.........ooo...................
   ...............ooo..........ooo.........oo....................
   ...............ooo..........o..........o.o....................
   .............................o................................
   .............................ooo..............................
   ................oo............................................
   ................oo............................................
   .....................o........................................
   ...................oooo......oo..oo...........................
   .............oo...o.o.oo.....oooo.o..o.o......................
   .............oo..o..o.ooo.....oo.o...o...o....................
   ..................o.o.oo....o............o.....oo.............
   ...................oooo..............o....o....oo.............
   .....................o...................o....................
   .....................................o...o....................
   .....................................o.o......................

:salvo: A collection of spaceships, usually gliders, all traveling in the same direction.  Any valid glider construction {recipe} can be partitioned into no more than four salvos.  Compare {flotilla}.

:seed:  A {constellation} of still lifes and/or oscillators, which can be converted into another Life object when it is struck by one or more gliders.  Usually the resulting object is a rare still life or spaceship, more complex than the original constellation.  {Spartan} single-glider (1G) seeds are more commonly seen than multi-glider seeds, because a Spartan 1G seed can be readily constructed and {trigger}ed using a {slow salvo}.  See also {freeze-dried salvo}.  For example, the following is a 14{sL} 1G seed for a c/7 loafer spaceship:.

       ...................................o..........
   ..................................o...........
   ..................................ooo.........
   .............oo...............................
   ..............o...............................
   ..............o.o.............................
   ...............oo.............................
   ..............................................
   ...o..........................................
   ..o.o.........................................
   .o.o..........................................
   .oo...........................................
   ..............oo..............................
   .............o.o..............................
   .............oo...............................
   ..............................................
   ..............................................
   ..............................................
   ....................oo........................
   ...................o.o........................
   ..........o.........o.........................
   .........o.o....o.............................
   ..........oo...o.o............................
   ..............o.o.............................
   ..............oo..............................
   ..............................................
   .............................................o
   .........................oo................ooo
   ....................oo...oo...............o...
   ...................o..o...................oo..
   .o.................o..o.......................
   o.o.................oo........................
   .oo...........................................
   ..............................................
   ..............................................
   ..............................................
   .....................oo.......................
   .....................o.o....oo................
   ......................o.....o.o...............
   .............................oo...............
   .................................oo...........
   .................................oo...........
   ..............................................
   ..............................................
   ......................oo......................
   .....................o..o.....................
   .....................o..o.....................
   ......................oo......................

:Seeds of Destruction Game:  An interactive search application written by Paul Chapman in 2013.  Its primary purpose was to assist in the design of self-destruct circuits in self-constructing circuitry.  It has also regularly been helpful in completing glider syntheses, and was used to find the {31c/240} base reaction for the {shield bug} and {Centipede} spaceships.

:self-constructing:  A type of pattern, generally a spaceship, that contains encoded construction information about itself, and makes a complete copy of itself using those instructions.  The {Gemini}, {linear propagator}, and {Demonoid}s are examples of self-constructing patterns.  Compare {self-supporting}.

:self-supporting:  A type of pattern, specifically a spaceship, that constructs {signals} or {tracks} or other scaffolding to assist its movement, but does not contain complete information about its own structure.  Examples include the {Caterpillar}, {Centipede}, {HBK} and {waterbear}.  Compare {self-constructing}.

:semi-Snark:  A small 90-degree glider reflector requiring two input gliders on the same lane for each output glider.  It was discovered by ‘Guam’ on 1 July 2013, using a custom-written search utility.  It functions as a very compact {period doubler} in signal circuitry -- see for example {linear propagator}.

:shield bug:  The first 31c/240 {macro-spaceship}, constructed by Dave Greene on September 9, 2014.

:signal elbow:  A {conduit} with  {signal} output 90 degrees from its input.  This term is commonly used only for {signal wires}, particularly {2c/3} signals.  A {Snark} could reasonably be called a “glider elbow”, but {glider reflector} is the standard term.  A signal elbow with a {recovery time} less than 20 ticks would enable a trivial proof that Conway’s Life is {omniperiodic}.  A relatively small {composite} {MWSS} elbow was discovered in 2015:
   ...TBD

:Simkin glider gun:  A {Herschel}-based period 120 glider gun discovered by Michael Simkin on TBD.

:sL: Still life.  This abbreviation is used most often in rough measurements of the complexity of a {Spartan} constellation.

:Snark: A small stable 90-degree glider reflector with a repeat time of 43 ticks, discovered by Mike Playle on 25 April 2013 using a search utility he wrote called {Bellman}. Compare {boojum reflector}.  Four common Snark variants are shown below -- Playle’s original (top), and variants by Heinrich Koenig, Simon Ekström, and Shannon Omick (left, bottom, and right, respectively):

   .............................oo....................
   ............................o.o....................
   ......................oo....o......................
   ....................o..o..oo.oooo..................
   ....................oo.o.o.o.o..o..................
   .......................o.o.o.o.....................
   .......................o.o.oo......................
   ........................o..........................
   ...................................................
   .....................................oo............
   ............................oo.......o.............
   ............................oo.....o.o.............
   .........o.........................oo..............
   .........ooo.......................................
   ............o........o.............................
   ...........oo.......o..............................
   ....................ooo............................
   ...................................................
   ...oo..............................................
   ...o.....................oo........................
   oo.o......................o........................
   o..ooo....oo...........ooo.........................
   .oo...o...oo...........o......................o....
   ...oooo.....................oo..............ooooo..
   ...o...............oo........o.............o.....o.
   ....ooo............o.o.......o.o............ooo..o.
   .......o.............o........oo...............o.oo
   ..ooooo..............oo.....................oooo..o
   .o..o......................o...........oo...o...oo.
   .oo......................ooo...........oo....ooo...
   ........................o......................o...
   ........................oo.....................o.oo
   ..............................................oo.oo
   ...................................................
   ...................................................
   ......................................oo...........
   ......................................o............
   .......................................ooo.........
   ..............oo.........................o.........
   .............o.o.....oo............................
   .............o.......oo............................
   ............oo.....................................
   ...................................................
   ..........................o........................
   ................oo....oo.o.o.......................
   ...............o..o..o.o.o.o.......................
   ................oo...o.o.o.oo......................
   ..................oooo.oo..o.......................
   ..................o...o....o.......................
   ...................o..o.ooo........................
   ....................o.o.o..........................
   .....................o.............................

:SODGame:  {Seeds of Destruction Game}

:space nonfiller:  Any pattern that expands indefinitely to affect every cell in the Life plane, but leaves an expanding region of {vacuum} at its center.  Compare {spacefiller}; see also {antstretcher}.  The first nonfiller was discovered by Jason Summers on 14 April 1999:

    ...................ooo...............
    ..................o..o...............
    ............ooo......o....ooo........
    ............o..o.o...o....o..o.......
    ............o..o.o...o....o..o.......
    ..........o..........o..o.o.ooo......
    ..........oo..oo..o.o....o.....o.....
    ........o................oo..ooo.....
    ........ooo.o.oo..........o......o...
    ......o........o.........o.o...ooo...
    ......ooo.....o..........o........o..
    ...o.o.........................o.ooo.
    ..ooooo.o..........................o.
    .oo......o.....................ooooo.
    oo....oo..................o.o........
    .o.o...o..o...............o..o...o.o.
    ........o.o..................oo....oo
    .ooooo.....................o......oo.
    .o..........................o.ooooo..
    .ooo.o.........................o.o...
    ..o........o..........o.....ooo......
    ...ooo...o.o.........o........o......
    ...o......o..........oo.o.ooo........
    .....ooo..oo................o........
    .....o.....o....o.o..oo..oo..........
    ......ooo.o.o..o..........o..........
    .......o..o....o...o.o..o............
    .......o..o....o...o.o..o............
    ........ooo....o......ooo............
    ...............o..o..................
    ...............ooo...................

:spaceship: +add more links to new spaceships.  TBD

:Sparse Life:  TBD

:Spartan:  TBD

:still life: +add {Spartan} link somewhere.  TBD.

:step: +... or {tick}

:superlinear growth:  TBD (applies to population growth, e.g., for {breeders} and {spacefillers}, and also to the reproduction rate of a {replicator}.  Due to limits enforced by the {speed of light}, no finite pattern can grow at a rate faster than quadratic.)

:swimmer lane:  See {bobsled}.

:switch-engine ping-pong: A very large (210515×183739) {quadratic growth} pattern found by Michael Simkin in October 2014, currently the smallest known.

:syringe:  A small stable glider-to-Herschel converter found by Tanner Jacobi on 19 March 2015.  the fastest safe repeat time is 78, but a following distance of 74 or 75 ticks will also work.

:toggle circuit:  Any signal-processing {circuit} that switches back and forth between two possible states or outputs .  An example is the following alternating H-to-G {converter}:
   ...TBD

:toggleable gun:  TBD

Example by Dean Hickerson, September 4, 1996:

    ..............oo..............o..
    ..............o.o.............o.o
    ..............o...............oo.
    .................................
    .................................
    .................................
    .................................
    ...............o..o....b.........
    .oooo..............o..b..........
    o...o..........o...o..bbb........
    ....o...........oooo.............
    o..o........................aaa..
    ............................a....
    .............................a...

In the figure above, glider B and an LWSS are about to send a glider NW.  Glider A will delete the next glider after B, turning off the output stream.  But if the device were already off, B wouldn't be present and A would instead delete the leading LWSS, turning the device back on.

:transparent lane:  A path through a signal-producing {circuit} that can be used to merge signal streams.  The signal -- usually a {standard spaceship} such as a {glider} -- can either be produced by the circuit, or it can come from elsewhere, passing safely through on the transparent lane without interacting with the circuit.

:TOLLCASS: Acronym for {The Online Life-Like CA Soup Search}.

:The Online Life-Like CA Soup Search:  A distributed search effort set up by Nathaniel Johnston in 2009, using a Python script running in {Golly}.  Results included a collection of the longest-lived 20x20 soups, as well as a census of over 174 billion {ash} objects.  Compare {Catagolue}.

:track: +the active {signal} object

:trigger:  TBD.

:universal computer: ... that is knowN TO be universal.

In 2009 Adam P. Goucher constructed a programmable {Spartan} universal computer/constructor pattern using stable {Herschel} circuitry.  TBD (included a minimal {single-arm}  universal constructor as well).

:universal constructor: + It *_is_* likely that it could be programmed to be construct itself,
Progressively smaller universal-constructor mechanisms have been used in the {linear propagator}, {spiral growth} pattern and the {Demonoid}s.

+Another strange consequence of the existence of universal constructors was pointed out by Adam P. Goucher in 2015.  Any glider-constructible pattern, no matter how large, can be constructed with a fixed number of gliders, probably less than ten thousand.  This can be done by working out a construction recipe for some type of {sliding block memory} with a faraway block, attached to a universal constructor.  The block’s position encodes an integer value that can be processed to retrieve as many bits of information as are needed to build a :1G seed:.  Eventually, after a completely unreasonable number of ticks, the seed can be {trigger}ed to produce the glider salvos which interact to construct the actual object.

:true: +update list of true-period guns.  TBD

:UC:  See {universal constructor}.

:universal toolkit:  A set of Life reactions and mechanisms that can be used to construct any object that can be constructed by glider collisions.

:waterbear:  an oblique spaceship discovered by Brett Berger on December 28, 2014. It is the smallest known oblique spaceship in terms of bounding box, superseding the {Parallel HBK}. It is currently the fastest oblique spaceship in Conway's Game of Life by several orders of magnitude.  Previous oblique spaceships, the {Gemini} and the {half-baked knightship}s, are stationary throughout almost all of their life cycles, as they construct the necessary mechanisms to support a sudden short move.  The waterbear constructs support for {(23,5)c/79} reactions which are in constant motion.

:wave:  TBD

:wavestretcher:  TBD

zweiback:  + could show a pattern using Scot Ellison’s HW volcano:

x = 41, y = 25, rule = B3/S23
10bo$8b5o17bo$7bo5bo14b5o$7bo2b2obo13bo5bo$3bob3obobob2o12bob2o2bo$3b
2o4bo16b2obobob3obo$6b2ob2o20bo4b2o$b5obobo2bo17b2ob2o$o6bo3bobo14bo2b
obob5o$2o2b5ob2obo13bobo3bo6bo$12b2o13bob2ob5o2b2o$5b2o4b3o13b2o$5b2o
4b3o5b2o6b3o4b2o$12b2o4bo2bo5b3o4b2o$2o2b5ob2obo5bobo5b2o$o6bo3bobo6bo
6bob2ob5o2b2o$b5obobo2bo14bobo3bo6bo$6b2ob2o17bo2bobob5o$3b2o4bo20b2ob
2o$3bob3obobob2o16bo4b2o$7bo2b2obo12b2obobob3obo$7bo5bo13bob2o2bo$8b5o
14bo5bo$10bo17b5o$30bo!

There's a considerably bigger collection of TBD's (To Be Done) in this half, but it's still a vaguely manageable job as long as I can resist adding too much more new stuff. We'll see how it goes. The next progress report will probably be a single ZIP file.

If anyone wants to fill in a TBD or two, now's your chance... again, RLE is fine, I'll convert it.
dvgrn
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Re: Life Lexicon update

Postby fluffykitty » February 11th, 2016, 12:20 pm

dvgrn wrote:...
... 24-cell quadratic growth: A 39786×143 {quadratic growth} pattern found by Michael Simkin in October 2014, two days after {26-cell quadratic growth} and a week before {switch-engine ping-pong}. ...
...
26 cell? You probably meant 25 cell.
Send those gliders to the quadratic replicator. It'll like them.
Also in "pi climber", triple-dots got turned into ellipses. At least on Textedit, Edit->Substitutions->Smart Dashes seems to fix it.
I like making rules
fluffykitty
 
Posts: 291
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Re: Life Lexicon update

Postby dvgrn » February 11th, 2016, 9:12 pm

dvgrn wrote:I'm offering a bounty of 256 gliders to anyone who finds an error...

fluffykitty wrote:26 cell? You probably meant 25 cell...
Also in "pi climber", triple-dots got turned into ellipses. At least on Textedit, Edit->Substitutions->Smart Dashes seems to fix it.

Argh. Don't know why I didn't notice those ellipses before. That's one of the sillier of the StupidReplace(TM) conventions -- in the last two decades there hasn't been a single time when I typed three periods and really wanted them automatically replaced by a single Unicode character.

Anyway, I've fixed both problems, I believe, and here are your 256 gliders -- since I don't have a quadratic replicator quite yet, because I'm stuck fixing up the Life Lexicon, because nobody seems to be writing definitions for me:

x = 746, y = 623, rule = B3/S23
742bo$740b2o$741b2o8$737bo$735b2o$736b2o8$732bo$730b2o$731b2o8$727bo$
725b2o$726b2o8$722bo$720b2o$721b2o8$687bo29bo$685b2o28b2o$686b2o28b2o
8$682bo29bo$680b2o28b2o$681b2o28b2o8$677bo29bo$675b2o28b2o$676b2o28b2o
8$672bo$670b2o$671b2o3$702bo$700b2o$701b2o3$667bo$665b2o$666b2o3$697bo
$695b2o$696b2o$o$b2o$2o660bo$660b2o$661b2o$10bo$11b2o$10b2o3$20bo$21b
2o$20b2o635bo$655b2o$656b2o$30bo$31b2o$30b2o5$622bo29bo$620b2o28b2o$
621b2o28b2o13$602bo44bo$600b2o43b2o$601b2o43b2o8$617bo24bo$615b2o23b2o
$616b2o23b2o3$582bo$580b2o$581b2o3$597bo14bo$595b2o13b2o$596b2o13b2o8$
562bo$560b2o$561b2o$40bo4bo4bo4bo4bo4bo4bo4bo4bo4bo4bo$41b2o3b2o3b2o3b
2o3b2o3b2o3b2o3b2o3b2o3b2o3b2o$40b2o3b2o3b2o3b2o3b2o3b2o3b2o3b2o3b2o3b
2o3b2o485bo$575b2o$576b2o$100bo$101b2o$100b2o490bo$590b2o$591b2o$110bo
$111b2o$110b2o3$120bo$121b2o$120b2o420bo14bo$540b2o13b2o$541b2o13b2o$
130bo$131b2o$130b2o440bo$570b2o$571b2o3$517bo19bo$515b2o18b2o$516b2o
18b2o8$552bo$550b2o$551b2o3$502bo$500b2o$501b2o8$532bo$530b2o$447bobo
81b2o$447b2o$448bo$282bobo202bo$283b2o200b2o$283bo202b2o3$512bo$510b2o
$442bobo66b2o$442b2o$443bo$287bobo207bo$288b2o205b2o$288bo207b2o3$472b
o9bo$470b2o8b2o$437bobo31b2o8b2o$145bo4bo4bo4bo4bo4bo4bo4bo4bo4bo4bo
241b2o$146b2o3b2o3b2o3b2o3b2o3b2o3b2o3b2o3b2o3b2o3b2o240bo$145b2o3b2o
3b2o3b2o3b2o3b2o3b2o3b2o3b2o3b2o3b2o95bobo$293b2o$293bo5$432bobo$432b
2o$433bo$297bobo$298b2o$298bo5$332bobo$332b2o$333bo$207bobo$208b2o$
208bo123bobo$332b2o$333bo$217bobo$218b2o$218bo113bobo$332b2o$333bo$
227bobo$228b2o$228bo113bobo$342b2o$343bo$247bobo$248b2o$248bo93bobo$
342b2o$343bo$257bobo$258b2o$258bo83bobo$342b2o$343bo$267bobo$268b2o$
268bo73bobo$342b2o$343bo$277bobo$278b2o$278bo78bobo$357b2o$358bo$302bo
bo$303b2o$303bo58bobo$362b2o$363bo$317bobo$318b2o$318bo43bobo$362b2o$
363bo$327bobo$328b2o$328bo48bobo$377b2o$378bo$352bobo$353b2o$353bo21$
271bo$270b2o$270bobo$256bo$256b2o$255bobo38bo$295b2o$295bobo$271bo$
271b2o$270bobo58bo$330b2o$330bobo$296bo$296b2o$295bobo53bo$350b2o$350b
obo$306bo$306b2o$305bobo53bo$360b2o$360bobo$306bo$306b2o$305bobo73bo$
380b2o$380bobo$316bo$316b2o$198b2o115bobo83bo$199b2o199b2o$198bo201bob
o$326bo$326b2o$325bobo5$193b2o131bo$194b2o129b2o$193bo131bobo$241bo$
241b2o$240bobo118bo$360b2o$360bobo$266bo$266b2o$188b2o75bobo113bo$189b
2o189b2o$188bo191bobo$276bo$276b2o$275bobo133bo$410b2o$410bobo$296bo$
296b2o$183b2o110bobo128bo$184b2o239b2o$183bo241bobo$301bo$301b2o$300bo
bo5$178b2o171bo$179b2o169b2o$178bo171bobo$216bo$216b2o$215bobo153bo$
370b2o$370bobo$226bo$226b2o$173b2o50bobo153bo$174b2o204b2o$173bo206bob
o$226bo$226b2o$133b2o90bobo163bo$134b2o254b2o$133bo256bobo$226bo$226b
2o$123b2o43b2o55bobo173bo$124b2o43b2o229b2o$123bo44bo231bobo$226bo$
226b2o$113b2o110bobo193bo$114b2o304b2o$113bo306bobo$236bo$236b2o$103b
2o58b2o70bobo213bo$104b2o58b2o284b2o$103bo59bo286bobo$256bo$256b2o$93b
2o160bobo208bo$94b2o369b2o$93bo371bobo6b2o$261bo211b2o$261b2o212bo$
158b2o100bobo$159b2o$158bo330b2o$488b2o$490bo$88b2o301bo$89b2o299b2o$
88bo301bobo91b2o18b2o$176bo306b2o18b2o$176b2o307bo19bo$153b2o20bobo
228bo$154b2o249b2o$153bo251bobo111b2o$181bo336b2o$181b2o337bo$83b2o95b
obo248bo$84b2o344b2o$83bo346bobo$196bo$196b2o$148b2o45bobo253bo$149b2o
299b2o$148bo301bobo46b2o$206bo291b2o$206b2o292bo$78b2o125bobo273bo$79b
2o399b2o$78bo401bobo$226bo$226b2o$225bobo268bo$495b2o$495bobo41b2o3b2o
$231bo306b2o3b2o$231b2o307bo4bo$73b2o155bobo$74b2o$73bo440b2o$513b2o$
515bo$421bo$420b2o$420bobo141b2o$146bo416b2o$146b2o417bo$68b2o75bobo
288bo$69b2o364b2o$68bo366bobo96b2o$151bo381b2o$151b2o382bo$33b2o115bob
o308bo$34b2o424b2o$33bo426bobo96b2o$166bo391b2o$166b2o392bo$23b2o38b2o
100bobo313bo$24b2o38b2o414b2o$23bo39bo416bobo101b2o$176bo406b2o$176b2o
407bo$13b2o160bobo333bo$14b2o494b2o$13bo496bobo41b2o$196bo356b2o$196b
2o357bo$3b2o53b2o135bobo328bo$4b2o53b2o464b2o$3bo54bo466bobo51b2o$201b
o376b2o$201b2o377bo$200bobo2$604b2o$603b2o$605bo$53b2o396bo$54b2o394b
2o$53bo396bobo121b2o$116bo456b2o$116b2o457bo$115bobo353bo$470b2o$470bo
bo126b2o$126bo471b2o$126b2o472bo$48b2o75bobo353bo$49b2o429b2o$48bo431b
obo141b2o$126bo496b2o$126b2o497bo$125bobo363bo$490b2o$490bobo101b2o$
126bo466b2o$126b2o467bo$43b2o80bobo373bo$44b2o454b2o$43bo456bobo$126bo
$126b2o$125bobo383bo$510b2o$510bobo101b2o3b2o$126bo486b2o3b2o$126b2o
487bo4bo$125bobo398bo$525b2o$525bobo$131bo$131b2o$130bobo423bo$555b2o$
555bobo$151bo$151b2o$150bobo418bo$570b2o$570bobo81b2o3b2o3b2o3b2o3b2o
3b2o3b2o3b2o$156bo496b2o3b2o3b2o3b2o3b2o3b2o3b2o3b2o$156b2o497bo4bo4bo
4bo4bo4bo4bo4bo$155bobo2$644b2o3b2o$643b2o3b2o$645bo4bo43$709b2o3b2o3b
2o3b2o3b2o3b2o3b2o3b2o$708b2o3b2o3b2o3b2o3b2o3b2o3b2o3b2o$710bo4bo4bo
4bo4bo4bo4bo4bo3$699b2o3b2o$698b2o3b2o$700bo4bo!
[[ STEP 10 ]]

EDIT: Just in case anyone wants to try it out, here's the script I threw together to build that silly recipe:

# build-block-thing-from-selection.py
import golly as g

r=g.getselrect()
if r==[]: g.exit("No selection.")
clist=g.getcells(r)
if len(clist)==0: g.exit("No cells.")
pat=[]
block=g.parse("oo$oo!")
blockrecipe=g.parse("261b2o$261b2o257$519b2o$519bobo$519bo$b2o$obo$2bo!",-261,0)
for i in range(0,len(clist),2):
  x,y=clist[i],clist[i+1]
  pat+=g.transform(blockrecipe,5*x,5*y)
  pat=g.evolve(pat,20)
g.addlayer()
g.setrule("LifeHistory")

g.putcells(pat,100,100)
g.fit()

It only works for small patterns. For arbitrarily large constructions, you'd have to adjust the "blockrecipe" pattern to move the gliders farther away from each other, in a way that would take more than thirty seconds to write. My time budget for this project was kind of short.
dvgrn
Moderator
 
Posts: 3991
Joined: May 17th, 2009, 11:00 pm
Location: Madison, WI

Re: Life Lexicon update

Postby dvgrn » March 1st, 2016, 2:32 am

Now that February is safely over -- the ten-year anniversary of the last Life Lexicon update, plus a day (due to the leap year) -- it's time for another progress update.

Even with the extra day, all the definitions didn't quite get done. Could still use a little help here.

Have had at least a quick look at everything in the Pattern of the Year collections, and added information on most of the patterns that seem likely to get looked up by Lexicon users.

Contributions of definitions for other new terms would be welcome. I'll post a complete file of all the new additions soon, and then will start work on combining new and old definitions, hunting for references with no referent, seeing if I can still get Stephen Silver's HTML-building code to run a decade later, and so forth.

After that there will be one more call for new definitions. Besides the Patterns of the Year, what other sources of new Life terminology would be good to look through, or think about?

EDIT: It turns out there are 889 definitions in the current draft Life Lexicon, so with all the new material added, there will be well over a thousand entries. Maybe I'll try for 1,111.
dvgrn
Moderator
 
Posts: 3991
Joined: May 17th, 2009, 11:00 pm
Location: Madison, WI

Re: Life Lexicon update

Postby thunk » March 30th, 2016, 12:28 am

In a crude attempt to make either more or less work for Dave, I have decided to fill in a few of the gaps in his updated definitions for the Lexicon (set off by percent signs):

Part 1:
Remove “14-ner”, “2 eaters”, move “4 boats” to “four boats”

:1G seed:  See {seed}.

:(23,5)c/79:  The rate of travel of the {Herschel climber} reaction used in the {self-supporting} {waterbear} {oblique spaceship}.

:24-cell quadratic growth: A 39786×143 {quadratic growth} pattern found by Michael Simkin in October 2014, two days after {25-cell quadratic growth} and a week before {switch-engine ping-pong}.

:25-cell quadratic growth:  A 25-cell quadratic growth pattern found by Michael Simkin on October 2014, with a bounding box of 21372×172. It was the smallest-population quadratic growth pattern for two days, until the discovery of {24-cell quadratic growth}. It superseded {26-cell quadratic growth}, which had held the record for eight years.

:26-cell quadratic growth:  a quadratic growth pattern found by Nick Gotts in March 2006, using ideas found in {metacatacryst} and {Gotts dots}.  It held the record for the smallest-population quadratic growth pattern for eight years, until it was surpassed by {25-cell quadratic growth}.

:31c/240:  The rate of travel of the {Herschel-pair climber} reaction used in the {Centipede} and {shield bug} {macro-spaceship}s.

:56P6H1V0: A 56-cell spaceship discovered by Hartmut Holzwart in 2009, the smallest known c/6 orthogonal spaceship as of this writing (March 2016).

:60P5H2V0: A 60-cell 2c/5 spaceship discovered by Tim Coe in May 1996.  It was the first non-c/2 orthogonal spaceship to be successfully constructed via {glider synthesis}.

:AK94 gun: %a {gun} that is the smallest to use the {AK-47} reaction, found by Mike Playle in May 2013 using his {Bellman} program.

+include cells below

:anteater:  +Matthias Merzenich discovered a c/5 anteater on 15 April /2011.  Connecting this to a standard diagonal {antstretcher} created a new oblique {wavestretcher} (a type of {growing spaceship}) and also an alternate {space nonfiller} mechanism.

   .......................................................o.....
   .......................................................oo....
   .....................................................o..o....
   ....................................................o........
   .................................................oo..o.......
   ................................................o..o.........
   .................................................o...........
   .............................................o...oo..........
   ............................................o.oo.............
   ...........................................oo..o.............
   ...........................................oo.oo.............
   ...........................................o..o..oo..........
   ..........................................oo......oo.........
   ...........................................o.oo.o.oo.........
   ..........................................o.ooo.o............
   ..........................................o.o.o.o............
   .............................................................
   ........................................o...o................
   .......................................oo....................
   .....................................ooo..o..................
   ..................................oo.oo......................
   ...................................o.........................
   ....................................o.o......................
   ...................................o.........................
   ...................................o..o......................
   ..................................o..........................
   .....................................o.......................
   ..................................oooo.......................
   ................................o.oo.o.......................
   .....................................o.......................
   ................................o............................
   .................................o..o........................
   ...................................o.........................
   .........................o....ooo....................ooo.....
   oo......................o.ooo....o......................o...o
   ..oo.oo.................o..o....o....................o...o...
   ..oo...oo.oo...............o..o................oo.o...o.oooo.
   oo.....oo...oo.oo.........oo.ooo...oo..oo.ooo.o....o.....o..o
   .....oo.....oo...oo.oo......o.oo..o.o..ooo.oo.o.o...o......o.
   ..........oo.....oo...oo.o...o....o.o.o..oo..o..o...oooo.....
   ...............oo.....oo..o.o.oo..o..o.......................
   ....................oo...........o....o..........oo...oo.....
   .......................................o..........o..........
   ....................................o........................
   ....................................oo.......................

A supporting c/5 {spark} is required at the right edge.  It can be supplied by a {spider} or another c/5 orthogonal spaceship with a similar {side spark}.

:antstretcher: -- Add Nicolay Beluchenko and Hartmut Holzwart’s example from 11 Jan 2006:

   ......................................................oo.......
   .....................................................oo........
   ...............................................oo.....o........
   ..............................................oo.....oo........
   ................................................o....o.o..oo...
   ..................................................oo...oo.oooo.
   ..................................................oo..........o
   ..............................................................o
   ........................................................o......
   ..........................................................oo...
   ...............................................................
   ..........................................................ooo..
   .........................................................oo..o.
   ...............................oo..........................o...
   ..............................oo...............................
   ...............................o.o...................ooo..o....
   ..........................o....ooo...................o..ooo....
   .........................ooooo.ooo..o.oo................oo.....
   .........................o..oo......o...oo.oo.........oo.oo....
   ...................................o....oo...oo.oo.......oo....
   ...........................oo..oo.oo..oo.....oo...oo.o.o.......
   ...................................o.......oo.....oo...........
   .....................ooo...o.....oo.............oo....o........
   .....................o.....o..o.oo...................o.........
   ......................o...oo.o.................................
   .........................oo...o.o..............................
   .............ooo..........o....................................
   .............o.....ooo..oo.....................................
   ..............o..oo.ooo.oo.....................................
   ................o..........o...................................
   .................o.o.oo....o...................................
   ...................oo.o........................................
   .................oo...o.o......................................
   ................oo.............................................
   ..................o............................................
   ...............oo..............................................
   ..............ooo..............................................
   .............oo.o..............................................
   ............oooo.o.............................................
   .................ooo...........................................
   ..................oo...........................................
   ..........ooo.oo...............................................
   .........o...ooo...............................................
   ............ooo................................................
   ........o.o.o..................................................
   .......oooo....................................................
   .......o.......................................................
   ........oo.....................................................
   .........o..o..................................................
   oo.............................................................
   o.o...ooo......................................................
   o...o....o.....................................................
   ...oo..........................................................
   ...o.....o.....................................................

:ark: +fix the thing about “five known arks”, wherever that was

:arm:  +See also {construction arm}.

:armless: A method of generating {slow salvo}s across a wide range of lanes without using a {construction arm} with a movable {elbow}.  Instead, streams of gliders on two fixed opposing {lanes} collide with each other to produce clean 90-degree output gliders.  Slowing down one of the streams by 8N ticks will move the output lanes of the gliders toward the source of that stream by N {full diagonal}s.  This construction method was used to create the supporting slow salvos in the {half-baked knightship}s, and also in the {Parallel HBK gun}.

:B59H:  One of the earliest and most remarkable {converter}s, discovered by Dave Buckingham in July 1996.  In 59 generations it transforms a B-heptomino into a clean Herschel with very good clearance, allowing easy connections to other conduits.  It forms the final stage of many of the known {composite conduit}s, including the majority of the original sixteen {Herschel conduit}s.  Here a {ghost Herschel} marks the output location:
%
o..oo.........
.ooo......oo.o
..o.......o.oo
..............
...oo.........
...oo.........
..............
..............
..............
..............
..............
..............
..............
..............
..............
..............
..............
..............
..............
..............
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..ooo.........
..o...........
.oo...........
%

:B60:  A {Herschel conduit} discovered by Michael Simkin in 2015 using his search program, {CatForce}.  It is one of two known {Blockic} Herschel conduits.  After 60 ticks, it produces a Herschel rotated 180 degrees at (x,y) relative to the input.  It can most easily be connected to another B60 conduit, producing a closed loop, the {Simkin glider gun}.

   o...........oo.....oo
   ooo.........oo.....oo
   ..o..................
   ..o............oo....
   ...............oo....
   .....................
   .....................
   .....................
   .....................
   ......o..............
   ......o.o............
   ......ooo............
   ........o............

:B-track:  -The term is more-or-less synonymous with Herschel track
A B-heptomino becomes a Herschel plus a block in twenty generations, so this term was nearly synonymous with {Herschel track} until the discovery of {elementary conduits} that convert a B directly to another B, or to some other non-Herschel signal output.  See for example {BRx46B}.

:Bellman:  a program for searching catalytic reactions, developed by Mike Playle, which successfully found the {Snark} and the {AK94 gun}.

:boat-bit:  move “In January 1997...” below the pattern.

:block pusher: -- add context from construction arm mechanisms?

:boojum reflector:  -- no longer the smallest known.  It was the smallest and fastest known stable reflector until the discovery of the {rectifier} in 2009.

:Bx125: One of the original sixteen {Herschel conduit}s, discovered by Paul Callahan in November 1998.  After 125 ticks, it produces an inverted {Herschel} rotated 180 degrees at (-9, -17) relative to the input.  Its {recovery time} is 166 ticks.  A {ghost Herschel} in the pattern below marks the output location:

   ...........................o..........
   ..o.......................o.o.........
   ..o.......................o.o.........
   ooo.........oo...........oo.ooo.......
   o...........oo.................o......
   .........................oo.ooo.......
   .........................oo.o.........
   ......................................
   ......................................
   ......................................
   ......................................
   ......................................
   ......................................
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   ......................................
   ....................................oo
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   ......................................
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   .........o.o..........................
   .........ooo..........................
   ...........o..........................
   ......................................
   .......................oo.............
   .......................o..............
   ........................ooo...........
   ..........................o...........

:Bx222: One of the original sixteen {Herschel conduit}s, discovered by Paul Callahan in October 1998.  After 222 ticks, it produces a backward-traveling inverted {Herschel} at (6, -16) relative to the input.  Its {recovery time} is 271 ticks.  A {ghost Herschel} in the pattern below marks the output location:

   .............o............................
   ....oo.....ooo.......oo...................
   .....o....o..........o....................
   .....o.o...o..........o...................
   ......o.o...o........oo...................
   .......o...oo.................o......o....
   ............................ooo.....o.o...
   ...........................o........o.o...
   ...........................oo......oo.ooo.
   .........................................o
   ..o...............oo...............oo.ooo.
   ..o...............oo...............oo.o...
   ooo.......................................
   o.........................................
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   ..........................................
   ........................................oo
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   ......................................o.o.
   ......................................oo..
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   ..........................................
   ..........................................
   ......o...................................
   ......o.o.................................
   ......ooo.................................
   ........o....................oo...........
   .............................o............
   ..................oo..........o...........
   ..................oo..oo.....oo...........
   ......................o.o.................
   ........................o.................
   ........................oo................

:catacryst: +mention newer superlinear growth patterns -- {wedge grow}, {26-cell quadratic growth}, {25-cell quadratic growth}, {24-cell quadratic growth}, and {switch-engine ping-pong}.

:Catagolue: An online database of objects in Conway's Game of Life and similar cellular automata, set up by Adam P. Goucher in 2015. It gathers data from a distributed search of random initial configurations and records the eventual decay products.  Within a year of operation it had completed a census of the {ash} objects from over two trillion asymmetric 16x16 soups, which can be found at at http://catagolue.appspot.com.

:CatForce:  An optimized search program written by Michael Simkin in 2015, using brute-force enumeration of small {Spartan} objects in a limited area, instead of a depth-first tree search.  One major purpose of CatForce is to find glider-constructible completions for signal conduits.  An early CatForce discovery was the {B60} conduit, which enabled a record-breaking new glider gun.

:Centipede:  the smallest known {31c/240} spaceship, constructed by Chris Cain on September 4, 2014 %as a refinement of the {shield bug}%.

:Caterpillar: is it still _by far_ the largest and most complex pattern ever constructed?  Just in terms of population, not bounding box, correct?

-- Add links to other Caterpillar-type constructions:  {Centipede}, {waterbear}, {31c/240}?, {shield bug}?, {half-baked knightship}, {Parallel HBK}

:circuit:  Any combination of {conduit}s or {converter}s that moves or processes an active signal.  This includes components with multiple states such as {period multiplier}s or {switch}es, which can be used to build {logic gate}s, {universal constructor}s, and other computation or construction circuitry.

:clearance:  In signal circuitry, the distance from an {edge-shooter} output lane to the last unobstructed lane adjacent to the edge-shooter circuitry.  For example, an {Fx119 inserter} has an unusually high 27{hd} clearance:

:clock insertion:  a uniquely effective method of adding a glider to the front edge of a {salvo}, by first constructing a {clock}, then converting it to a glider using a one-bit {spark}.  Here it rebuilds a sabotaged eater in a deep pocket between other gliders:

   ..................................................o........
   ..................................................o.o......
   ..................................................oo.......
   ...............................................o......o....
   ..............................................o......o.....
   ..............................................ooo....ooo...
   ...........................................................
   ...........................................o......o........
   ...........................................o.o....o.o.....o
   ...........................................oo.....oo....oo.
   ........................................o.......o........oo
   .......................................o...................
   .......................................ooo...........o.o...
   .....................................................oo....
   ......................................................o....
   o..................................................o.......
   .oo..............................................oo........
   oo................................................oo.......
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   ...........................................................
   .............................o.............................
   ....................o......o.o.............................
   ..................o.o.......oo.............................
   ...................oo......................................
   .........................o.................................
   ..........................o....ooo.........................
   ........................ooo....o...........................
   ................................o..........................
   .....................................oo....................
   ............................oo.......o.o...................
   ............................o.o......o.....................
   ............................o..............................
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   .............................................oo............
   .............................................o.o...........
   .............................................o.............

In 2015 Chris Cain used this reaction to demonstrate conclusively that any unidirectional glider {salvo}, no matter how large or tightly packed, can be constructed by collisions between gliders that are initially separated by any finite distance.  As a corollary, because all glider syntheses are made up of two to four unidirectional salvos, any glider-constructible object has a synthesis that starts with every glider at least N cells away from every other glider (for any chosen N).

:Coe ship: +mention that it’s the first non-p4 spaceship ever seen emerging from an asymmetrical random {soup} configuration.
%In late 2015, the Coe ship was discovered in an asymmetric random {soup} on {Catagolue}. This was the first time any non-p4 ship was discovered in soup, winning Adam Goucher a 50-euro prize given by Ivan Fomichev.%

:colour-preserving: See {colour of a glider}.  A {Snark} is a colour-preserving reflector.

:colour-changing: See {colour of a glider}.  The period-8 reflector shown in {reflector} is colour-changing, as are its p4/5/6/7 and higher-period versions.

:component: A partial {glider synthesis} that can be used in the same way in multiple {recipe}s.  A component transforms part of an object under construction in a well-defined way, without affecting the rest of the object.  For example, this well-known component can be used to add a {hook} to any object that includes a protruding {table} end, converting it to a {long bookend}:

   .......o...................o...................o
   .....oo..................oo..................oo.
   ......oo..................oo..................oo
   ................................................
   ..o...................o...................o.....
   o.o.................o.o.................o.o.....
   .oo..o...............oo..o...............oo..o..
   .....o.o.................o.o.................o.o
   .....oo..................oo..................oo.
   ................................................
   ................................................
   ....................o...........................
   ...o..o............o.o.o..o............oo..o..o.
   ...oooo.............oo.oooo............o...oooo.
   ......................o.................ooo.....
   .....oo...............o.o.................o.o...
   .....oo................o.o.................oo...
   ........................o.......................

:composite:  See {composite conduit}.

:composite conduit:  A signal-processing {conduit} that can be subdivided into two or more {elementary conduits}.

:compression: See {recovery time}.

:colorized Life: -> colourised (%probably, best to use en-UK throughout%)

:conduit: %Over several hundred {elementary conduits} are now known, with more being discovered every month through search programs such as {CatForce} and {Bellman}.% [Remove sample conduit, move to {B59H} in standard orientation.]

:conduit 1: {B59H}.

:construction arm:  An adjustable mechanism in a {universal constructor} that allows new objects to be constructed in any chosen location that the arm can reach.  A construction arm generally consists of a {shoulder} containing fixed guns or edge shooters, a movable {construction elbow} that slides forward and backward along the {construction lane}(s), and in the case of {single-arm} universal constructors, a {hand} target object at the construction site that can be progressively modified by a {slow salvo} to produce each desired object.

:construction elbow:  One of the components of a {construction arm} in a {universal constructor}.  The elbow usually consists of a single {Spartan} still life or small constellation.  It accepts {elbow operation} {recipe}s, in the form of {salvo}s coming from the construction arm’s {shoulder}.

These recipes may do one of several things:  1) {pull} the elbow closer to the shoulder, 2) {push} the elbow farther from the shoulder, 3) emit a glider or other {spaceship} on a particular output {lane} (while also optionally pushing or pulling the elbow); 4) create a “{hand}” target block or other useful object to one side of the {construction lane}; 5)  duplicate the elbow, or 6) destroy the elbow.

If a mechanism can be programmed to generate recipes for at least the first three options listed above, it is generally capable of functioning as a {universal constructor}.  The main requirement is that push and pull {elbow operations} should be available that are either minimal (1{fd}) or the distances should be relatively prime.

Depending on the {elbow operation} library, there may be only one type of elbow, or there may be two or more elbow objects, with recipes that convert between them.  The {9hd} library had just one elbow type, a block.  The original {10hd} library had two elbows, blocks in mirror-symmetric locations; this was expanded to a larger list for the {10hd Demonoid}.  The {0hd Demonoid} also has a multi-elbow recipe library.

If only one color, parity, or phase of glider can be emitted, then the mechanism will be limited to producing {monochromatic salvo}s or {monoparity salvo}s.  These are less efficient at most construction tasks, but are still generally accepted to enable {universal toolkit}s.  See also {half-baked knightship}.

:construction envelope: the region affected by an active reaction, such as a {glider construction} of an object.  The envelope corresponds to the state-2 blue cells in {LifeHistory}.  See also {edgy}.

:construction lane:  Part of a {construction arm} between the {shoulder} and the {elbow} -- in particular, one of the fixed {lane}s that {elbow operation} signals travel on.  All known {universal constructor}s have used arms with two or more construction lanes, except for the {0hd Demonoid} and {single-lane construction} recipes.

%:copperhead: A c/10 orthogonal {spaceship} with only 28 cells found in March 2016 by conwaylife.com forum member zdr using a search program of their own creation. Simon Ekström later found a {sparky} {tagalong} for the copperhead that same month, allowing for the construction of c/10 puffers and rakes. The copperhead with and without the tagalong is shown below:

....oo...........oo....
...oooo.........oooo...
.......................
..oooooo.......oooooo..
...oooo.........oooo...
.......................
..oo..oo.......oo..oo..
oo.o..o.oo...oo.o..o.oo
...o..o.........o..o...
.......................
.......................
....oo...........oo....
....oo...........oo....
.......................
.o.o..o.o..............
o..o..o..o.............
o........o.............
o........o.............
oo......oo.............
..oooooo...............
%

:crab:  See {quarter}.

:converter:  +The following diagram shows a multi-stage {B-heptomino} to {Herschel} to {MWSS} to {glider} converter.  {Ghost Herschel}s mark the inputs and outputs of the {R64} {Herschel conduit}s.  The first stage is {B59H}, the Herschel-to-MWSS stage was discovered by Tanner Jacobi in October 2015, and the MWSS-to-glider stage was found by Matthias Merzenich in July 2013:

..................................oo............
...................................o...oo.......
..................................o....oo.......
..................................oo............
....................................o...........
..................................ooo...........
.................................o..............
.................................oo.............
................................................
................................................
................................................
................................................
................................................
................................................
................................................
................................................
................................................
................................................
.......oo..............................ooo......
.......oo..............................o..o.....
.......................................o........
.......................................o...o....
.oo....................................o........
.oo.....................................o.o.....
.....oo.........................................
.....oo...............o.........................
......................o......................o..
......................ooo.oo................o.o.
........................o.oo................o.o.
oo...........................................o..
oo..............................................
................................................
................................................
................................................
................................................
................................................
................................................
..............oo...........................o....
..............o...........................o.o...
............ooo...........................oo....
................................................
................................................
................................................
................................................
................................................
................................................
........................o.....................oo
........................ooo..................oo.
..........................o...............oo..oo
..........................o...............oo...o
................................................
................................................
................................................
.....oo.........................................
.....oo.....................oo..................
...........oo...............o................oo.
...........oo................ooo..............o.
...............................o.............o..
.............................................oo.
.........oo.....................................
.........oo.....oo..............................
................oo..............................

:dart: +A 25-glider recipe for the dart was found in December 2014 %by Martin Grant and Chris Cain%, making it the first glider-constructible c/3 spaceship.

:Demonoid:  The first self-constructing diagonal spaceship. A 0{hd} Demonoid was completed by Chris Cain in December 2015, shortly after a much larger 10{hd} version constructed the previous month in collaboration with Dave Greene. The 0hd spaceship fits in a bounding box about 55,000 cells square, and displaces itself by 65 cells diagonally every 438,852 generations.

The first 0hd Demonoid was fired by a gun.  As of this writing (2016) this is the only case where a spaceship’s gun pattern was completed before the first appearance of the actual spaceship.

:dependent conduit:  A {Herschel conduit} in which the input {Herschel} interacts with catalysts in the first few ticks -- technically at T=-3, before the Herschel is completely formed.  Compare {independent conduit}.  The Herschel is prevented from emitting its {first natural glider}, This is useful in cases where the previous conduit cannot survive a first natural glider emitted from its output Herschel.

This term is somewhat confusing, since it is actually the previous conduit that depends on the dependent conduit to suppress the problematic glider.  Dependent conduits such as the {F166} and {Lx200} do not actually depend on anything.  They can be freely connected to any other conduits that fit, as long as the output Herschel evolves from its standard great-grandparent.  As of this writing, the {Fx158} is the only known case where a conduit’s output Herschel has an alternate great-grandparent, which is incompatible with dependent conduits’ initial transparent block.

:double wing: +The term is no longer in use.

:dove: Found in 2015 to be a possible active reaction for the input or output of a {converter}.
%
ooo..
o..o.
.o..o
..oo
%
:dragon:  Remove “All other known orthogonal c/6 spaceships are flotillas involving at least two dragons”... With 102 cells, it was the smallest known orthogonal c/6 spaceship until Hartmut Holzwart discovered {56P6H1V0} in April 2009.

:drain trap: +The term is no longer in use.

eater(2): “two different directions” is an odd way of putting it -- that’s more the TWIT-eater’s specialty. Update the TWIT pattern to show this, and give it its own entry, adding Chris Cain’s Spartan from-the-side eater also.

eater2: +“Can eat gliders arriving on any of four adjacent {lane}s.”

%:eater5: A compound eater that can eat gliders coming from two different directions. Also called the tub-with-tail eater (TWIT), it is often placed on the edges of {conduits} to suppress unwanted gliders. Below is the standard form, a compact form with a {long hook}, and an often-useful conjoined form found with {Bellman}.

.......oo...........
...o...oo....o...oo.
..o.o.......o.o...o.
.o.o.......o.o...o..
.o.........o....o...
oo........oo.....ooo
...................o
....................
.o...oo.............
o.o...o.............
oo...o..............
....o...............
ooooo.o.............
o....o.o............
..o..o.o............
.oo...o.............

Chris Cain found a {Spartan} eater with the same functionality as the eater 5 in (2013?), shown below.

......o......
.....o.o.....
....o..o...oo
.....oo....oo
.o...........
o.o..........
oo...........
......oo.....
......oo.....
%

:edgy:  in slow-salvo terminology, an “edgy” glider construction recipe is one that places its final product at or very near the edge of its construction envelope.

remove :eaters +:

:egg:  +The term is no longer in common use.

:elbow:  This term may refer to a {signal elbow} or a {construction elbow}.  See also {elbow ladder}.

:elbow operation:  A {glider recipe} traveling on one or more {construction lane}s, that collides with an elbow constellation and performs one of the standard transformations on it -- push, pull, emit, construct, duplicate, or delete.  See {construction elbow}.
Last edited by thunk on March 30th, 2016, 12:29 am, edited 1 time in total.
"What's purple and commutes?
The Evanston Express."
thunk
 
Posts: 165
Joined: October 3rd, 2015, 8:50 pm
Location: Central USA

Re: Life Lexicon update

Postby thunk » March 30th, 2016, 12:28 am

Part 2:

:elementary conduit:  A {conduit} with no recognizable active signal stage besides its input and output.  Theoretically an elementary conduit may become a composite conduit, if another conduit can be found that shares the beginning or end of the conduit in question.  In practice this happens very rarely, because many of the most likely branch points have already been identified:  standard spaceship, Herschel, B-heptomino, R-pentomino, pi, queen-bee shuttle, %century (or bookend), and wing.%

:envelope: {construction envelope}

:F116: One of the original sixteen {Herschel conduit}s, discovered by Paul Callahan in February 1997.  After 116 ticks, it produces a {Herschel} at (32, 1) relative to the input.  Its {recovery time} is 138 ticks; this can be reduced to 120 ticks by adding extra mechanisms to suppress the internal glider.  It is {Spartan} only if the following conduit is a {dependent conduit}, so that the {welded} {FNG} eater can be removed.  A {ghost Herschel} in the pattern below marks the output location:

   ........o..........................
   ........ooo........................
   ...........o.......................
   ..........oo.......................
   ...................................
   ...................................
   ...................................
   ...................................
   ...................................
   ...................................
   ...................................
   ...................................
   ...................................
   ...................................
   o..................................
   o.o.............................o..
   ooo.............................o..
   ..o.............................ooo
   ..................................o
   ...................................
   ...................................
   ...................................
   ...................................
   .........................oo........
   ...................oo.....o........
   ...................o.o.ooo.........
   ............oo.......o.o...........
   ............oo.......oo............

:F117: One of the original sixteen {Herschel conduit}s, discovered by Dave Buckingham in July 1996.  After 117 ticks, it produces a {Herschel} at (40, -6) relative to the input.  Its {recovery time} is 63 ticks.  It can be made {Spartan} by replacing the snake with a fishhook eater in one of two orientations.  A {ghost Herschel} in the pattern below marks the output location:

   ......................oo.....................
   .......................o.....................
   ..........o...........o......................
   ..........ooo.........oo.....................
   .............o...............................
   oo..........oo...............................
   .o...........................................
   .o.o.........................................
   ..oo.........................................
   .........................oo...............o..
   .........................oo...............o..
   ..........................................ooo
   ............................................o
   .............................................
   .............................................
   ..o..........................................
   ..o.o........................................
   ..ooo........................................
   ....o...........oo...........................
   ................o............................
   .................ooo.........................
   ...................o.........................

:F166: One of the original sixteen {Herschel conduit}s, discovered by Paul Callahan in May 1997.  Along with the {Lx200}, it is one of the two original {dependent conduits} (several more have since been discovered).  After 166 ticks, it produces a {Herschel} at (49, 3) relative to the input.  Its {recovery time} is 116 ticks.  A {ghost Herschel} in the pattern below marks the output location.  It can be made {Spartan} by replacing the snake with a fishhook eater in one of two orientations.  The input shown here is a Herschel great-grandparent, since the Herschel is catalysed by the {transparent} block before its standard form appears:

   .................................oo.....................
   ..................................o.....................
   .................................o......................
   .................................oo.....................
   ........................................................
   ........................................................
   .oo.....................................................
   ooo.oo..................................................
   .oo.ooo.oo..............................................
   ooo.oo..oo..........................oo...............o..
   oo..................................oo...............o..
   .....................................................ooo
   .......................................................o
   ........................................................
   ........................................................
   ........................................................
   ......oo................................................
   .....o.o......................................oo........
   .....o.........................................o........
   ....oo.........................oo...........ooo.........
   ...............................oo...........o...........
   ........................................................
   ........................................................
   .................oo.....................................
   ..................o.....................................
   ...............ooo......................................
   ...............o........................................
   ...........................oo...........................
   ...........................o............................
   ............................ooo.........................
   ..............................o.........................

:F171: The seventeenth {Herschel conduit}, discovered by Brice Due in August 2006 in a search using only {eaters} as {catalyst}s.  This was the first new Herschel conduit discovery since 1998.  After 171 ticks, it produces a {Herschel} at (29, -17) relative to the input.  Its {recovery time} is 227 ticks, slower than many of the original sixteen conduits because of the delayed destruction of a temporary blinker, though it is clearly {Spartan}.  A {ghost Herschel} in the pattern below marks the output location:

   ..........o......................
   ..........ooo....................
   .............o...................
   ............oo...................
   .....o...........................
   .....ooo.........................
   ........o........................
   .......oo........................
   .................................
   ..............................o..
   ....oo........................o..
   .....o........................ooo
   .....o.o........................o
   ......oo.........................
   .................................
   .................................
   o................................
   ooo..............................
   ...o.............................
   ..oo.............................
   .................................
   .................................
   .................................
   .................................
   .................................
   .................................
   .o...............................
   .o.o.............................
   .ooo.............................
   ...o.............................
   .................................
   ..........oo.....................
   ...........o.....................
   ........ooo......................
   ........o........................

:fd:  Abbreviation for {full diagonals}.

:first natural glider:  The glider produced at T=21 during the evolution of a {Herschel}.  This is the most common signal output from a {Herschel conduit}.

:FNG:  See {first natural glider}.

:freeze-dried salvo: A constellaton of constructible objects which, when {trigger}ed by a single glider, produces a unidirectional glider {salvo}, and nothing else.  Freeze-dried salvos can be useful in {slow salvo} constructions, especially when an active circuit has to destroy or reconstruct itself.  The freeze-dried form can be considered to be a single-glider {seed} for the target salvo.

:French kiss: +For many years this was one of the best-known small oscillators with no known {glider synthesis}.  In October 2013 Martin Grant completed a 23-glider construction.

:frozen:  See {freeze-dried salvo}.

:full diagonals:  Diagonal measurement appropriate whenever an adjustable mechanism is present

:Fx119:  One of the original sixteen {Herschel conduit}s, discovered by Dave Buckingham in September 1996.  After 119 ticks, it produces an inverted {Herschel} at (20, 14) relative to the input.  Its recovery time is 231 ticks; this can be reduced somewhat by suppressing the output Herschel’s glider, or by adding extra {catalysts} to make the reaction settle more quickly. A {ghost Herschel} in the pattern below marks the output location:

   o......................
   o.o....................
   ooo....................
   ..o....................
   .......................
   .......................
   .......................
   .......................
   .......................
   .......................
   .......................
   .......................
   .......................
   .......................
   .......................
   .........oo...........o
   ....oo...oo.........ooo
   ....oo..............o..
   ....................o..
   .......................
   ...oo..................
   ....o....oo............
   .ooo.....oo............
   .o.....................

:Fx119 inserter:  A Herschel-to-glider converter and {edge shooter} based on an {Fx119}  Herschel conduit:

   .........o....................
   .........o.o..................
   .........ooo..................
   ...........o..................
   ..............................
   ..............................
   ..............................
   ..............................
   ..oo......oo..................
   ...o.......o..................
   ooo.....ooo...................
   o.......o.....................
   ..............................
   ..............................
   ..............................
   ..................oo..........
   .............oo...oo..........
   .............oo...............
   ..............................
   ..............................
   ............oo............oo..
   .............o....oo......o...
   ..........ooo.....oo.......ooo
   ..........o..................o

:Fx77: One of the original sixteen {Herschel conduit}s, discovered by Dave Buckingham in August 1996.  After 77 ticks, it produces an inverted {Herschel} at (25, -8) relative to the input.  Its {recovery time} is 61 ticks; this can be reduced slightly by suppressing the output Herschel’s glider, as in the {L112} case.  A {pipsquirter} can replace the blinker-suppressing eater to produce an extra glider output.  It is one of the simplest known {Spartan} conduits, and one of the few {elementary conduits} in the original set of sixteen.  A {ghost Herschel} in the pattern below marks the output location:

   o............................
   ooo..........................
   ...o.........................
   ..oo...........oo...........o
   ...............oo.........ooo
   ..........................o..
   ..........................o..
   .............................
   .............................
   .............................
   .o...........................
   .o.o.........................
   .ooo.........................
   ...o.........................
   .............................
   .............................
   .............................
   .............................
   .............................
   ................oo...........
   ................o.o..........
   ..................o..........
   ..................oo.........
   
% in 2016, Tanner Jacobi discovered a {Spartan} method of extracting an extra glider output from the Fx77, shown below:

   o............................
   ooo..........................
   ...o.........................
   ..oo...........oo...........o
   ...............oo.........ooo
   ..........................o..
   ..........................o..
   .............................
   .............................
   .............................
   .o...........................
   .o.o.........................
   .ooo.........................
   ...o.........................
   .............................
   .............................
   .............................
   .............................
   .............................
   ...........oo......oo........
   ..........o..o.....oo........
   ..........o..o...............
   ...........oo................
%

:Fx153: One of the original sixteen {Herschel conduit}s, discovered by Paul Callahan in February 1997.  After 153 ticks, it produces an inverted {Herschel} at (48, -4) relative to the input.  Its {recovery time} is 69 ticks.  It can be made {Spartan} by replacing the snake with a fishhook eater in one of two orientations.  A {ghost Herschel} in the pattern below marks the output location:

:Fx158: One of the original sixteen {Herschel conduit}s, discovered by Dave Buckingham in July 1996.  After 158 ticks, it produces an inverted {Herschel} at (27, -5) relative to the input.  Its {recovery time} is 176 ticks.  It is the only known conduit that does not produce its output Herschel via the usual great-grandparent, so it cannot be followed by a {dependent conduit}.  A {ghost Herschel} in the pattern below marks the output location:

:Fx176: One of the original sixteen {Herschel conduit}s, discovered by Paul Callahan in October 1997.  After 176 ticks, it produces an inverted {Herschel} at (45, 0) relative to the input.  Its {recovery time} is 92 ticks.  A {ghost Herschel} in the pattern below marks the output location:

   ..............................oo..................
   ..............................oo..................
   ..................................................
   .................oo...............................
   ..................o...............................
   ..................o.o.............................
   ...................oo.............................
   ..................................................
   ..................................................
   ..............oo..................................
   ......o.......oo..................................
   ......ooo.........................................
   .........o........................................
   ........oo........................................
   ..................................................
   oo................................................
   .o................................................
   .o.o.....................................oo.......
   ..oo......................................o.......
   ..........................................o.o.....
   ...........................................o.o....
   ............................................o...oo
   ................................................oo
   ..................................................
   ..................................................
   ..o...............................................
   ..o.o...............................oo...........o
   ..ooo...............................oo.........ooo
   ....o..........................................o..
   ...............................................o..
   ..............oo........oo........................
   ..............oo..oo.....o........................
   ..................o.o.ooo.........................
   ....................o.o...........................
   ....................oo....oo......................
   .........................o.o....oo................
   .........................o......oo................
   ........................oo........................

:Game of Life News:  A blog reporting on new Life discoveries, started by Heinrich Koenig in December 2004, currently found at http://pentadecathlon.com/lifenews/.
+[Maybe write to Koenig, see if he's planning to shut that link down any time soon...]

:Garden of Eden: +The following shows a 10x10 Garden of Eden found by Marijn Heule, Christiaan Hartman, Kees Kwekkeboom, and Alain Noels in 2013 using SAT-solver techniques.  An exhaustive search of 90-degree rotationally symmetric 10x10 patterns was possible because the symmetry reduces the number of unknown cells by a factor of four.

   .o.ooo.o..
   ..o.o.o..o
   o.ooo..oo.
   .o.ooooo.o
   o..o..oooo
   oooo..o..o
   o.ooooo.o.
   .oo..ooo.o
   o..o.o.o..
   ..o.ooo.o.

:Gemini: The first {self-constructing} spaceship, and also the first {oblique} spaceship, traveling at a speed of (5120,1024)c/33699586.  It was made public by Andrew Wade on 18 May 2010.  It was the thirteenth explicitly constructed spaceship velocity in Life, and made possible an infinite family of related velocities.  The Gemini spaceship derives its name from the Latin “gemini”, meaning twins, describing its two identical halves, each of which contains three Chapman-Greene {construction arms}. A tape of gliders continually relays between the two halves, instructing each to delete its parent and construct a daughter configuration.

:Geminoid: %A {spaceship} or other {self-constructing} pattern that is derived from Andrew Wade's {Gemini}. Geminoid {knightships} with different velocities have been constructed, and the design was the basis for Dave Greene's {linear propagator} and the {Demonoid}s.%

:ghost Herschel:  A {dying spark} made by removing one cell from the {Herschel} heptomino.  This particular spark has the advantage that, when placed in a conduit to mark the location of an input or output Herschel, it disappears cleanly without damaging adjacent catalysts, even in {dependent conduit}s.

   o..
   o..
   ooo
   ..o

:Golly:  +does anything need adding?  Multistate rules, unbounded and bounded grids, etc? Seems pretty good the way it is, really.

:Gotts dots: A 41-cell 187×39 {superlinear growth} pattern, O(t ln(t)), found by Bill Gosper in March 2006.  Collisions within the pattern cause it to sprout its Nth {switch engine} at generation T = ~224n-6.

:half-bakery reaction:  the key reaction used in the {half-baked knightship} and {parallel HBK}, where a half-bakery is moved by (6,3) when a glider collides with it, and the glider continues on a new lane.  Pairs of these reactions at the correct relative spacing can create 90-degree output gliders, %as noticed by Ivan Fomichev in May 2014%:
%
.............................o.
............................o..
............................ooo
...............................
...............................
...............................
...............................
...............................
...............................
...............................
....................oo.........
...................o..o........
...................o.o.........
.................oo.o..........
........o.......o..o...........
......oo........o.o............
.......oo........o.............
...............................
....oo.........................
...o..o........................
...o.o.........................
.oo.o..........................
o..o...........................
o.o............................
.o.............................
%

:half-baked knightship:  %This was the first spaceship to be constructed, in December 2014 by Adam Goucher, based on the {half-bakery} reaction. Moving at a speed of (6,3)c/2621440, it is one of the slowest known {knightships}, and the first one that was not a {Geminoid}. Chris Cain optimized the design a few days later to create the Parallel HBK.%

:half-diagonals:  TBD

:Halfmax:   A pattern that acts as a spacefiller in half of the Life plane, found by Jason Summers in May 2005. It expands in three directions at c/2, producing a triangular region that grows to fill half the plane.

:hashlife: -It is not, however, suitable for showing a continuous display of the evolution of a pattern.  Add mention of {Golly}. %Tomas Rokicki implemented Hashlife into Golly in TK_YEAR.%

:H-to-G: A {Hershel-to-glider} converter.

:HBK:  {half-baked knightship}

:hd:  Abbreviation for {half-diagonals}.

:hand:  Any object used as a {slow salvo} {target} by a {construction arm}.

:helix:  +Give speed for the example helix.

:Herschel:  +Herschels are one of the most versatile types of {signal} in stable circuitry.  {R-pentomino}es and {B-heptomino}es naturally evolve into Herschels, and {converters} have also been found that change {pi heptomino}es and several other signal types into Herschels, and vice versa.  See {elementary conduit}.

:Herschel receiver:  +Any {circuit} that converts two incoming gliders on parallel {lanes} into a Herschel signal.  The following diagram shows a...

:Herschel climber: The following glider-supported reaction used in the {waterbear}, which can be repeated every 79 ticks, moving the Herschel 23 cells to the right and 5 cells upward, and releasing two gliders to the northwest and southwest:

...............o.o...............o..
...............oo...............o.o.
................o...............o..o
.................................oo.
....................................
....................................
....................................
....................................
....................................
....................................
....................................
....................................
o...................................
o.o.................................
ooo.................................
..o.................................
%
As the diagram shows, it is possible to substitute a loaf or other still lifes for some or all of the support gliders.  This fact is used to advantage at the front end of the {waterbear} spaceship.

:Herschel conduit:  -Sixteen simple stable Herschel conduits are currently known, having been discovered from 1995 onwards by Dave Buckingham (DJB) and Paul Callahan (PBC).
+More than fifty simple stable Herschel conduits are currently known.  The exact number depends on the definition of "simple".  In general a Herschel conduit can be called "simple" if its active reaction does not return to a  Herschel stage except at its output.  Compare {elementary conduit}, {composite conduit}.

The original {universal} set consisted of sixteen stable Herschel conduits, discovered between 1995 and 1998 by Dave Buckingham (DJB) and Paul Callahan (PBC).

{R64}    R   -11   9   DJB, Sep 1995
{Fx77}   Ff   -25   -8   DJB, Aug 1996
{L112}   L   -12  -33   DJB, Jul 1996
{F116}   F   -32   1   PBC, Feb 1997
{F117}   F   -40   -6   DJB, Jul 1996
{Bx125}   Bf    9  -17   PBC, Nov 1998
{Fx119}   Ff   -20   14   DJB, Sep 1996
{Fx153}   Ff   -48   -4   PBC, Feb 1997
{L156}   L   -17  -41   DJB, Aug 1996
{Fx158}   Ff   -27   -5   DJB, Jul 1996
{F166}   F   -49   3   PBC, May 1997
{Fx176}   Ff   -45   0   PBC, Oct 1997
{R190}   R   -24   16   DJB, Jul 1996
{Lx200}   Lf   -17  -40   PBC, Jun 1997
{Rx202}   Rf   -7   32   DJB, May 1997
{Bx222}   Bf    6  -16   PBC, Oct 1998

TBD: Break down each composite Herschel conduit of the original set of sixteen:  e.g., L156 = HLx69R + RF28B + {B59H}.  Won't take much more space.  Not going to define HLx69R or any of the hundred-and-umpteen other named elementary conduits, just B59H as a prime example of the breed (the LifeWiki has it as “Conduit 1”, and it was already in the Life Lexicon as “probably the most remarkable conduit”.)

:Herschel-to-glider converter: The largest category of {elementary conduit}.  Gliders are very common and self-supporting, so it’s much easier to find these than any other type of output {signal}.  A large collection of H-to-G converters has been compiled, with many different output {lane}s and timings.  These can be used to synchronize multiple signals to produce {gun} patterns or complex logic circuitry.  See {NW31T120} for an example.

:Herschel-pair climber:  The mechanism defining the rate of travel of the {Centipede} and {shield bug} spaceships.  Compare {pi climber}.  It consists of a pair of {Herschels} climbing two parallel chains of blocks.  Certain spacings between the block chains allow gliders from each Herschel to delete the extra ash objects produced by the other Herschel.  Another glider escapes to each side, leaving only an exact copy of the original block chains, but shifted forward by 9 cells:

   oo.........................................................oo
   oo.........................................................oo
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   oo.........................................................oo
   oo.........................................................oo
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .............................................................
   .......................................................ooo...
   .......................................................o..o..
   .......................................................o..o..
   ......................................................oooo...
   .......ooo............................................oo.....
   ........o............................................o.......
   ......ooo.............................................o......
   ......................................................o......

:highway robber: any mechanism that can retrieve a signal from a spaceship {lane} while allowing spaceships on nearby lanes to pass by unaffected.  In practice the spaceship is generally a glider.  The signal is removed from the lane, an output signal is generated elsewhere, and the highway robber returns to its original state.  A competent highway robber does not affect gliders even on the lane adjacent to the affected glider stream, except during its recovery period.

A perfect highway robber doesn’t affect later gliders even in the lane to which it is attached, even during its recovery period.  Below is a near-perfect highway robber “bait” that requires three synchronized signals to rebuild (the {Herschel}, {B-heptomino}, and {glider}.)  The glider at the top right passes by unharmed, but another glider following on the same {lane} 200 ticks later will be cleanly reflected to a new path -- and another glider following that one will also pass by unharmed.  The only imperfection is a few ticks at the very end of the reconstruction, as the beehive is being rebuilt::

   ......................o...........o.........
   ......................ooo.......o.o.........
   .........oo...oo.........o.......oo.........
   .........oo...oo........oo..................
   ............................................
   ............................................
   ..oo........................................
   ...o........................................
   ...o.o......................................
   ....oo......................................
   ............................................
   ............................................
   ............................................
   ............................................
   ............................................
   ............................................
   .......oo...................................
   ........o...................................
   .....ooo....................................
   .....o......................................
   ............................................
   ............................................
   ............................................
   ............................................
   ............................................
   ............................................
   ....................oo......................
   ....................oo......................
   ............oo..............................
   .............o..............................
   o.........ooo...............................
   ooo.......o.................................
   ...o........................................
   ..oo........................................
   ............................................
   ............................................
   ............................................
   ............................................
   ...........o...........oo...............oo..
   .........ooo..........o.o...............oo..
   .........o.o............o...................
   .........o.....................oo.o.......o.
   ...............................o.oo......ooo
   ........................................oo.o
   ............................................
   .............................oo.............
   .............................oo.............
   .......................oo...................
   .......................oo...................
   ............................................
   ............................................
   .........................oo.................
   ..................oo.....oo.................
   ..................oo........................

:HW volcano: +At least four progressively smaller forms of this sparker have been found, including a 25-cell-wide version found by David Eppstein in 2003, and a vertically narrower 28-cell-wide version by Karel Suhajda in 2004.  Scot Ellison’s 17-cell-wide version is shown in the {zweiback} entry.
"What's purple and commutes?
The Evanston Express."
thunk
 
Posts: 165
Joined: October 3rd, 2015, 8:50 pm
Location: Central USA

Re: Life Lexicon update

Postby thunk » March 30th, 2016, 12:29 am

Part 3 (apologies for the serial posting, I couldn't get under the character limit otherwise):
:independent conduit:  A {Herschel conduit} in which the input Herschel produces its {first natural glider}.  Compare {dependent conduit}.

:infinite growth: +add link to {quadratic growth}

:intermediate target:  A temporary product of a partial {slow salvo}, {elbow operation}, or {glider synthesis}.  An intermediate target is a useful step toward a desired outcome, but will not appear in the final construction.

:kickback: +Another two-glider collision also produces a 180-degree output glider.  This can also be referred to as a kickback reaction, though it is used less often in constructions because the gliders come from opposite directions:

   .o.
   o..
   ooo
   ...
   ...
   .oo
   o.o
   ..o

:knightship: %A {spaceship} that moves in the (2,1) direction.% +The first Conway's Life knightship was a variant of Andrew Wade's Gemini spaceship, constructed in May 2010.  The next was an even slower knightship based on the {half-bakery reaction}.

:L112: One of the original sixteen {Herschel conduit}s, discovered by Dave Buckingham in July 1996.  After 112 ticks, it produces a {Herschel} turned 90 degrees counterclockwise at (12, -33) relative to the input.  Its {recovery time} is 61 ticks; this can be reduced slightly by removing the output glider, either with a specialized eater (as in the original {true} p59 gun), or with a {sparker} as in most of the {Quetzal} guns.  It can be made {Spartan} by replacing the {aircraft carrier} with a fishhook eater in one of two orientations.  A {ghost Herschel} in the pattern below marks the output location:

   ...............oo.......
   ...............o........
   .............ooo........
   ........................
   ........................
   ........................
   ........................
   ........................
   ........................
   ........................
   ........................
   ........................
   ........................
   ........................
   ........................
   ........................
   ........................
   ........................
   .............oo.........
   .............oo.........
   ....oo..................
   ....o..o................
   oo....oo................
   .o....................oo
   .o.o..................o.
   ..oo................o.o.
   ....................oo..
   ........................
   ........................
   ........................
   ........................
   ........................
   ..o.....................
   ..o.o...................
   ..ooo...................
   ....o...................
   ........................
   ..............oo........
   ..............oo..oo....
   ..................o.o...
   ....................o...
   ....................oo..

:L156: One of the original sixteen {Herschel conduit}s, discovered by Dave Buckingham in August 1996.  After 156 ticks, it produces a {Herschel} turned 90 degrees counterclockwise at (17, -41) relative to the input.  Its {recovery time} is 62 ticks.  It can be made {Spartan} by replacing the snake with a fishhook eater in one of two orientations.  A {ghost Herschel} in the pattern below marks the output location:

   ...................oo........
   ...................o.........
   .................ooo.........
   .............................
   .............................
   .............................
   .............................
   .............................
   .............................
   .............................
   .............................
   .............................
   .............................
   .............................
   .............................
   .............................
   .............................
   .............................
   .................oo..........
   .................oo..........
   .............................
   ........oo.o.................
   ........o.oo.................
   ..........................oo.
   ..........................o..
   ........................o.o..
   ........................oo...
   .............................
   .........o...................
   .........ooo.................
   o...........o................
   ooo........oo..............o.
   ...o......................o.o
   ..oo.......................o.
   .............................
   .............................
   .............................
   .............................
   .............................
   .............................
   .o....................oo.....
   .o.o..................o.o....
   .ooo....................o....
   ...o...........oo.......oo...
   ...............o.............
   ................ooo..........
   ..................o..........

:lane:  a path traveled by a glider, or less commonly, a spaceship such as a loafer.  The lane is centered on the line of symmetry (if any) of the spaceship in question.  If a lane is clear, then the spaceship can travel along it without colliding or interfering with any other objects.

Diagonal lanes are often numbered consecutively, in half-diagonals ({hd}).  Occasionally diagonal lane measurements are given in quarter-diagonals ({qd}), in part because diagonally symmetric spaceships have a line of symmetry 1qd away from the lines available for gliders.  It’s also convenient that moving a glider forward by 100qd (for example) has the same effect as evolving the same glider for 100 ticks.

:LifeHistory:  A multistate CA rule equivalent to two-state B3/S23 Life, but with several additional states intended for annotation purposes.  A “history” state records whether an off cell has ever turned on in the past, and other states allow on and off cells to be permanently or temporarily marked, without affecting the evolution of the pattern.

:lifesrc:  +A Java version, JavaLifeSearch, was written in November 2012 by Karel Suhajda.

:LifeViewer:  A scriptable Javascript Life pattern viewer written by Chris Rowett, used primarily on the conwaylife.com discussion forums.

:lightspeed wire: +TBD: Add Jason Summers' discovery of beehive lightspeed wire in October 2002.

:linear propagator: a self-replicating pattern in which each copy of a pattern produces one child that is an exact copy of itself.  The child pattern then blocks the parent from any further replication.   An example was constructed by Dave Greene on 23 November 2013.  By some definitions, due to its limited one-dimensional growth pattern, the linear propagator is not a true replicator; Compare {quadratic replicator}.

:loafer: a c/7 spaceship discovered by Josh Ball on 17 February 2013:

   .oo..o.oo
   o..o..oo.
   .o.o.....
   ..o......
   ........o
   ......ooo
   .....o...
   ......o..
   .......oo

It has a known 8-glider construction {recipe}, probably not minimal, discovered on the following day:

   .................................o
   ...............................oo.
   ................................oo
   .........o........................
   .o........o.......................
   ..o.....ooo.......................
   ooo...............................
   ..................................
   ..................................
   .....o............................
   ......o...........................
   ....ooo...........................
   ........................o.o.......
   .........................oo.......
   .........................o........
   ..................................
   ...........................o.o....
   ...........................oo.....
   ............................o.....
   ...............................ooo
   ...............................o..
   ................................o.
   ..................................
   ..................................
   ..................................
   ..................................
   ..................................
   ..................................
   .....oo...........................
   ......oo..........................
   .....o............................

The loafer was therefore the first new glider-constructible spaceship in almost a decade.  (A glider synthesis for a 2c/5 ship, 60P5H2V0, was found in March 2003.)

:Lx200: One of the original sixteen {Herschel conduit}s, discovered by Paul Callahan in June 1997.  Along with the {F166}, one of the two original {dependent conduits} (several more have since been discovered.)  After 200 ticks, it produces an inverted {Herschel} turned 90 degrees counterclockwise at (17, -40) relative to the input.  Its {recovery time} is 90 ticks.  It can be made {Spartan} by replacing the snakes with fishhook eaters in one of two orientations. A {ghost Herschel} in the pattern below marks the output location. The input shown here is a Herschel great-grandparent, since the Herschel is catalysed by the {transparent} block before its standard form appears:

   .....................oo.............
   ......................o.............
   ......................ooo...........
   ....................................
   ....................................
   ....................................
   ....................................
   ....................................
   ....................................
   ....................................
   ....................................
   ....................................
   ....................................
   ....................................
   ....................................
   ....................................
   ....................................
   ....................................
   .......................oo...........
   .......................oo...........
   ....................................
   ..............................o.oo..
   ..............................oo.o..
   ....................................
   ....................................
   ..............o.oo..................
   ..............oo.o..................
   ....................................
   ....................................
   ....................................
   ....................................
   ....................................
   ....................................
   ....................................
   ....................................
   ....................................
   ....................................
   ................................oo..
   ................................o.o.
   .oo...............................o.
   ooo.oo............................oo
   .oo.ooo.oo..........................
   ooo.oo..oo..........................
   oo..................................
   ....................................
   ....................................
   ....................................
   ................................oo..
   ................................oo..
   ....................................
   ......oo............................
   .......o............................
   ....ooo.........................oo..
   ....o...........................oo..
   ..................oo................
   .................o.o................
   .................o..................
   ................oo........oo........
   ..........................o.........
   ...........................ooo......
   .............................o......

:macro-spaceship: a {self-constructing} or {self-supporting} spaceship, such as the {Caterpillar}, {Centipede}, {half-baked knightship}, {waterbear}, and {Demonoid}.  Engineered spaceships of these types are inevitably large and complex.

:metacatacryst:  -This is currently the smallest known pattern (in terms of initial population) with superlinear growth.  +It was the smallest known pattern with superlinear growth, until the discovery (also by Gotts) of {26-cell quadratic growth}.

:metapixel:  See {OTCA Metapixel}.

:monochromatic salvo:  A {slow salvo} that uses gliders of only one {colour}.  For example, the slow salvos generated by {half-baked knightship}s are monochromatic, because they’re generated by a single type of reaction which can happen at any position along a diagonal line.  The smallest step is one {full diagonal} (1fd), which is two {half diagonal}s (2%h%d), so the glider-producing reaction can only reach half of the available lanes.

:monoparity salvo:   A {slow salvo} that uses gliders of only one {parity}.  Compare {monochromatic salvo}.

:NW31:  One of the most common stable {edge-shooter}s.  This Herschel-to-glider {converter} suppresses the junk ordinarily left behind by an evolving {Herschel} while allowing both the {first natural glider} and {second natural glider} to escape on {transparent lane}s:

   .......oo.......................
   ........o.......................
   ........o.o.....................
   .........oo.....................
   ................................
   ................................
   ................................
   ..............................oo
   ..............................oo
   ................................
   .........o......................
   .........o.o....................
   .........ooo....................
   ...........o....................
   ................................
   ................................
   ................................
   ................................
   ..oo............................
   ...o............................
   ooo.............................
   o...............................
   ....................oo..........
   ....................oo..........

:NW31T120: The full designator of {NW31}. The T120 timing measurement means that a canonical NW glider placed at time T=120, at (+31, +0) relative to the input Herschel, would reach the exact same spacetime locations as the converter's output glider (assuming no interference from the conversion circuitry).

:nonfiller: See {space nonfiller}

:omniperiodic:  TBD  +%No oscillators are known for periods 19, 23, 38, and 41; only trivial oscillators are known for period 17. Period 43 and 53 oscillators were made possible in 2013 by Mike Playle's {snark} = ;-recent discoveries no longer all found by Noam Elkies.

:one per generation:  See {grow-by-one object}.

:orphan:  -- TBD: distinguish from GoE according to modern usage:  TBD.  Is it something like, a GoE is the entire plane, where an orphan is just the ON and OFF cells needed to ensure no parent is possible?

:OTCA Metapixel: A 2048 × 2048 period 35328 {unit cell} constructed by Brice Due in 2006.  It contains a large “pixel” area that contains a large population of {LWSS} spaceships when the cell state is ON, but is empty when the cell state is OFF.  This allows the state of the cell to be visible at high zoom levels, unlike all previous unit cells where the state was signaled by the presence or absence of a single glider in a specific location.

:overclocking:  A term used in {staged-recovery circuit}s.  TBD %A term used when a {circuit} can accept a signal at a specific period which it cannot accept at a higher period. For instance, the {syringe} can be overclocked at periods of 74 or 75, faster than its ordinary period of 78%

:parity: Even or odd, particularly as applied to the {phase} of an oscillator or spaceship.  For example, in {slow salvo} constructions, the {intermediate target}s are frequently period 2 -- most often they contain {blinker}s or {traffic light}s.  A glider striking a P2 constellation will generally produce a different result depending on its parity.  Conversely, it doesn’t matter if an incoming glider is in phase 1 or phase 3, because period-4 intermediate targets are rare (or not used).  TBD...

:single-arm:  A type of {universal constructor} using just one construction arm and {slow-salvo} techniques to construct, usually, {Spartan} or near-Spartan circuitry.  Compare {two-arm}.

:shoulder: The fixed upper end of a {construction arm}, generally consisting of one or more glider {gun}s or {edge shooter}s aimed at an {elbow} object.

:target:  TBD

:two-arm:  TBD.  Original {Gemini} example.

:p5 reflector:  TBD

:p6 pipsquirter:  TBD

:p6 reflector:  TBD

:p7 pipsquirter:  TBD

:p7 reflector:  TBD

:p8 reflector:  %One of a family of {reflectors} found by Noam Elkies in 199?, containing a {figure-eight}, boat, eater, and block. Unlike the Snark, it is {color-changing}.%

:p8 G-to-H:  TBD

:parallel HBK:  A much smaller successor to the {half-baked knightship}, constructed by Chris Cain in September 2014.  Several slow-salvo recipes are needed to support the multi-glider salvo {seed}s at the upstream end of the spaceship.  "Parallel" means that these recipes are sent in parallel instead of one after the other, in series, as in the original HBK.


:parasite: A self-sustaining reaction attached to the output of a rake or puffer, that damages or modifies the standard output.  Compare {tagalong}.  In 2009, while experimenting with {novelty generating} patterns in {Golly}, Mitchell Riley discovered parasites on glider streams from p20 and p8 backward rakes.  In some cases, parasites can even “reproduce”, as in the pattern below, though the number of copies is limited since they will eventually use up their host glider stream:

   ......o.............o.........
   .....ooo...........ooo........
   ...oo.ooo.........ooo.oo......
   ....o..o.oo.....oo.o..o.......
   .oo.o....o.o...o.o....o.oo....
   .oo.o.o..o.oo.oo.o..o.o.oo....
   .o........o.o.o.o........o....
   oo.......oo.o.o.oo.......oo...
   ............o.o...............
   .......ooo.o...o.ooo..........
   ......oo...........oo.........
   ......o.....o....oo..o........
   .....oo....ooo...oo..o........
   ...........o.oo...ooo.........
   ............ooo....o..........
   ............ooo...............
   ............ooo...............
   ............oo................
   ..............................
   ...................o.o........
   ....................oo........
   ...............oo...o.........
   ........oo......oo............
   .......oo......o..............
   .........o....................
   ..............................
   ..............................
   .................oo...........
   ..........o......ooo..........
   .........ooo.o...ooo..........
   ........oo.o.....ooo..........
   ........oo......o.oo..........
   ........oo......ooo....oo.....
   ........oo.oo....o.....o......
   .........oo...........oo......
   ..........ooo.o...o.ooo.......
   ...............o.o............
   ...oo.......oo.o.o.oo.......oo
   ....o........o.o.o.o........o.
   ....oo.o.o..o.oo.oo.o..o.o.oo.
   ....oo.o....o.o...o.o....o.oo.
   .......o..o.oo.....oo.o..o....
   ......oo.ooo.........ooo.oo...
   ........ooo...........ooo.....
   .........o.............o......

:period multiplier:  A commonly used term for a {pulse divider}.  Dividing the number of {signal}s in a regular stream by N necessarily multiplies the {period} by N.  For Herschel signals, a number of small period doubler, tripler, and quadrupler mechanisms are known.  The term "period multiplier" can be somewhat misleading, because most such circuits can accept aperiodic input streams.

:pi climber:  The reaction that defines rate of travel of the {Caterpillar} spaceship.  A pi climber consists of a pi-heptomino “climbing” a chain of blinkers, moving 17 cells every 45 ticks, and leaving behind an identical chain of blinkers, shifted downward by 6 cells.  A single pi climber does not produce any gliders or other output, but two or more of them traveling on nearby blinker chains can be arranged to emit gliders every 45 ticks.  Compare {Herschel-pair climber}.
   ..o..
   ..o..
   ..o..
   .....
   .....
   .....
   .....
   .....
   .....
   .....
   .....
   .....
   .....
   .....
   .....
   ..o..
   .ooo.
   .o.o.

:pulse divider: +For n=2, the simplest known stable pulse divider is the {semi-Snark}.

:quadratic replicator:  A pattern that fills all or part of the Life plane by making copies of itself in a nonlinear way.  Small quadratic replicators are known in other Life-like rules, but no example has been found or constructed in Conway’s Life as of January 2016.

:quadratic growth: The fastest possible rate of population growth for a finite Life pattern -- O(t^2) in big-O notation, where t is the number of ticks.  See {superlinear growth}.

:quarter:  +the name is due to the minimum population of 25 cells.

:qd:  Abbreviation for {quarter-diagonals}.

:quadratic sawtooth:  TBD

:quarter-diagonals:  TBD

:R64: One of the original sixteen {Herschel conduit}s, discovered by Dave Buckingham in September 1995; also one of two known {Blockic} Herschel conduits.  After 64 ticks, it produces a {Herschel} rotated 90 degrees clockwise at (11, 9) relative to the input.  Its {recovery time} is 153 ticks, though this can be improved to 61 ticks by adding a from-the-side eater inside the turn to avoid interference from the output Herschel’s {first natural glider}, as shown below.  It is one of the simplest known {Spartan} conduits, one of the two known {Blockic} conduits, and one of the few {elementary conduits} in the original set of sixteen. A {ghost Herschel} in the pattern below marks the output location:

   .........oo...........
   .........oo.....oo....
   ................oo....
   ......................
   ......................
   ..............oo......
   ..............oo......
   ....................oo
   ....................oo
   ......................
   ......................
   ......................
   o.....................
   o.o...................
   ooo...................
   ..o...................
   ......................
   ......................
   ......................
   ..oo.oo...............
   o..o.o.o..............
   oo.o..o...............
   ...o........ooo.......
   ...oo.......o.........
   .oo..o.o...oo.........
   o..o..oo..............
   .oo...................

:recovery time:  The number of {ticks} that must elapse after a {signal} is sent through a {conduit}, before another signal can be safely sent on the same path.  In general, a lower recovery time means a more useful conduit.  For example, the {Snark}'s very low recovery time allowed for the creation of {oscillator}s with previously unknown {period}s, 43 and 53.

-- :receiver:, :transceiver:, :transmitter:   change "path" to "lane" and "tracks" to "lanes"

:rectifier: A 180-degree {reflector} discovered by Adam P. Goucher in 2009.  It has the same output glider as the {boojum reflector} but a much shorter {repeat time} of only 106 ticks.  Another advantage of the rectifier is that the output glider is on a {transparent lane}, so it can be used in logic circuitry to merge two signal paths.

   ..o.........................................
   o.o.........................................
   .oo.........................................
   ............................................
   ..............o.............................
   .............o.o............................
   .............o.o............................
   ..............o.............................
   ............................................
   ............................................
   ............................................
   ............................................
   ............................................
   ............................................
   ............................................
   ............................................
   ............................................
   ............................................
   ............................................
   .......................oo...................
   .......................oo...................
   ............................................
   .....oo.....................................
   ....o.o.....................................
   ....o.......................................
   ...oo.......................................
   ..................................oo........
   .................................o..o..oo...
   .................................o.o....o...
   ..............oo..................o.....o.oo
   .............o.o.....................oo.o.o.
   .............o.......................o..o..o
   ............oo....................o....o..oo
   ..................................ooooo.....
   ............................................
   ....................................oo.o....
   ....................................o.oo....
   ............................ooo.............
   ............................o...............
   .............................o..............

:reflector: - simplify early-history text...%The smallest known stable reflector is Mike Playle's {Snark}, with a recovery time of 43% %Playle has offered a $100 prize for a color-changing stable reflector contained within a 25 by 25 {bounding box} with a recovery time of 50 generations of less.%

:replicator: +%Dave Greene's {linear propagator} can be considered as the first example of a replicator built in Life, but this is debatable as its copies replicate themselves exactly once.%

:rle: +is now the usual means of exchanging Life patterns by e-mail or in online forum discussions.

:R190: One of the original sixteen {Herschel conduit}s, discovered by Dave Buckingham in July 1996.  After 190 ticks, it produces a {Herschel} turned 90 degrees clockwise at (24, 16) relative to the input.  Its {recovery time} is 107 ticks.  A {ghost Herschel} in the pattern below marks the output location:

   ..........oo.........................
   .......oo..o.........................
   .....ooo.oo..........................
   ....o................................
   .o..oooo.oo..........................
   .ooo...o.oo..........................
   ....o................................
   ...oo..........................oo....
   ...............................o.....
   .............................o.o.....
   .............................oo......
   .....................................
   .....................................
   .....................................
   .....................................
   .................................oo.o
   .................................o.oo
   .....................................
   o.........................oo.........
   o.o.......................oo.........
   ooo..................................
   ..o..................................
   .....................................
   .....................................
   .........oo...oo.....................
   ..........o...o......................
   .......ooo.....ooo...................
   .......o.........o...................
   .................o.o.................
   ..................oo.................
   .....................................
   .....................................
   .....................................
   .....................................
   .....................................
   .........................ooo.........
   .........................o...........
   ........................oo...........

:Rx202: One of the original sixteen {Herschel conduit}s, discovered by Dave Buckingham in May 1997.  After 202 ticks, it produces an inverted {Herschel} turned 90 degrees clockwise at (7, 32) relative to the input.  Its {recovery time} is 201 ticks.  A {ghost Herschel} in the pattern below marks the output location:

   ..............oo...............
   ...........oo..o...............
   .........ooo.oo......o.........
   ........o..........ooo.........
   .........ooo.oo...o............
   ...........o.oo...oo...........
   ...............................
   ...............................
   ...............................
   ...............................
   .......................oo......
   .......................o.......
   .....................o.o.......
   .....................oo........
   ...............................
   ...............................
   ...............................
   ...............................
   ...............................
   ...o...........................
   ...o.o.........................
   ...ooo.........................
   .....o.........................
   ......................oo.......
   ......................oo.......
   ...............................
   ...............................
   ...............................
   ...............................
   ...............................
   ...............................
   ...............................
   o.oo...........................
   oo.o...........................
   .....................oo........
   .........oo.........o..o..oo...
   .........oo.........o.o....o...
   .....................o.....o.oo
   ........................oo.o.o.
   ........................o..o..o
   .....................o....o..oo
   .....................ooooo.....
   ...............................
   ...................ooooooo.....
   ...................o..o..o.....
   .................o.o...........
   .................oo............
   ...............................
   ...............................
   ...............................
   ...............................
   ...............................
   .........ooo...................
   ...........o...................
   ...........oo..................

:sawtooth: +%The smallest known sawtooth currently has a minimum population of 177 cells, found by conwaylife.com forum user 'thunk', a slight modification of earlier designs by several other users.%

:SGR: +This term is no longer in use.

:SNG:  {second natural glider}.

:second natural glider:  The glider produced at T=72 during the evolution of a {Herschel}.  This is the common edge-shooting glider output used in the {NW31} converter and several other converter variants.

:signal: +Signals are used in Herschel circuitry, universal constructors, macro-spaceships...

:single-lane construction:  TBD

:switch:  TBD.  [Use the dependent-conduit ON/OFF switch as an example? What’s smaller?]

:switchable gun:  A {gun} that includes a mechanism to turn the output stream off and on with a simple signal, often a glider.  A small example is Dietrich Leithner’s switchable LWSS gun from July 8, 1995.  The ON signal enters from the northeast, and the OFF signal from the northwest:

   .................oo...........................................
   .................o..o.........................................
   ..............................................................
   .....................o........................................
   ..............................................................
   .o.................oo.........................................
   ..o...............o...........................................
   ooo...........................................................
   ..............................................................
   ...............oo...oo........................................
   ...............oo...oo........................................
   ................ooooo........................o................
   .................o.o........................o.................
   ............................................ooo...............
   .................ooo..........................................
   ....................................o.o.......................
   ....................................o...o.....................
   ........................................o.......o.............
   ..........................oo........o....o....oooo............
   ..........................oo............o....o.o.oo...........
   .....................o..............o...o...o..o.ooo........oo
   ......................o.............o.o......o.o.oo.........oo
   ....................ooo.......................oooo............
   ................o...............................o.............
   ...............ooo...................o........................
   ..............ooooo..................o.o.....o................
   .............oo...oo.................oo....ooo................
   ..........................................o...................
   .............................o............oo..................
   ...........................o..o.........ooo...................
   ...............ooo..........ooo.........oo....................
   ...............ooo..........o..........o.o....................
   .............................o................................
   .............................ooo..............................
   ................oo............................................
   ................oo............................................
   .....................o........................................
   ...................oooo......oo..oo...........................
   .............oo...o.o.oo.....oooo.o..o.o......................
   .............oo..o..o.ooo.....oo.o...o...o....................
   ..................o.o.oo....o............o.....oo.............
   ...................oooo..............o....o....oo.............
   .....................o...................o....................
   .....................................o...o....................
   .....................................o.o......................

:salvo: A collection of spaceships, usually gliders, all traveling in the same direction.  Any valid glider construction {recipe} can be partitioned into no more than four salvos.  Compare {flotilla}.

:seed:  A {constellation} of still lifes and/or oscillators, which can be converted into another Life object when it is struck by one or more gliders.  Usually the resulting object is a rare still life or spaceship, more complex than the original constellation.  {Spartan} single-glider (1G) seeds are more commonly seen than multi-glider seeds, because a Spartan 1G seed can be readily constructed and {trigger}ed using a {slow salvo}.  See also {freeze-dried salvo}.  For example, the following is a 14{sL} 1G seed for a c/7 loafer spaceship:.

       ...................................o..........
   ..................................o...........
   ..................................ooo.........
   .............oo...............................
   ..............o...............................
   ..............o.o.............................
   ...............oo.............................
   ..............................................
   ...o..........................................
   ..o.o.........................................
   .o.o..........................................
   .oo...........................................
   ..............oo..............................
   .............o.o..............................
   .............oo...............................
   ..............................................
   ..............................................
   ..............................................
   ....................oo........................
   ...................o.o........................
   ..........o.........o.........................
   .........o.o....o.............................
   ..........oo...o.o............................
   ..............o.o.............................
   ..............oo..............................
   ..............................................
   .............................................o
   .........................oo................ooo
   ....................oo...oo...............o...
   ...................o..o...................oo..
   .o.................o..o.......................
   o.o.................oo........................
   .oo...........................................
   ..............................................
   ..............................................
   ..............................................
   .....................oo.......................
   .....................o.o....oo................
   ......................o.....o.o...............
   .............................oo...............
   .................................oo...........
   .................................oo...........
   ..............................................
   ..............................................
   ......................oo......................
   .....................o..o.....................
   .....................o..o.....................
   ......................oo......................

:Seeds of Destruction Game:  An interactive search application written by Paul Chapman in 2013.  Its primary purpose was to assist in the design of self-destruct circuits in self-constructing circuitry.  It has also regularly been helpful in completing glider syntheses, and was used to find the {31c/240} base reaction for the {shield bug} and {Centipede} spaceships.

:self-constructing:  A type of pattern, generally a spaceship, that contains encoded construction information about itself, and makes a complete copy of itself using those instructions.  The {Gemini}, {linear propagator}, and {Demonoid}s are examples of self-constructing patterns.  Compare {self-supporting}.

:self-supporting:  A type of pattern, specifically a spaceship, that constructs {signals} or {tracks} or other scaffolding to assist its movement, but does not contain complete information about its own structure.  Examples include the {Caterpillar}, {Centipede}, {HBK} and {waterbear}.  Compare {self-constructing}.

:semi-Snark:  A small 90-degree glider reflector requiring two input gliders on the same lane for each output glider.  It was discovered by %Sergey 'Guam' Petrov% on 1 July 2013, using a custom-written search utility.  It functions as a very compact {period doubler} in signal circuitry -- see for example {linear propagator}.

   ......o..........oo
   .......oo........o.
   ......oo.......o.o.
   ...............oo..
   ..........o........
   oo.........oo......
   oo........oo.......
   ...................
   ...................
   .................oo
   ..........oo.....oo
   ..........oo.......
   ...................
   .....o.............
   ....o.o............
   ....oo......oo.....
   ............o......
   .............ooo...
   ...............o...

:shield bug:  The first 31c/240 {macro-spaceship}, constructed by Dave Greene on September 9, 2014.

:signal elbow:  A {conduit} with  {signal} output 90 degrees from its input.  This term is commonly used only for {signal wires}, particularly {2c/3} signals.  A {Snark} could reasonably be called a “glider elbow”, but {glider reflector} is the standard term.  A signal elbow with a {recovery time} less than 20 ticks would enable a trivial proof that Conway’s Life is {omniperiodic}.  A relatively small {composite} {MWSS} elbow was discovered in 2015:
   ...TBD

:Simkin glider gun:  A {Herschel}-based period 120 glider {gun} discovered by Michael Simkin on %April 28, 2015. With only 36 on cells, it ties with the {Gosper glider gun} as the smallest gun.

:sL: Still life.  This abbreviation is used most often in rough measurements of the complexity of a {Spartan} constellation.

:Snark: A small stable 90-degree glider reflector with a repeat time of 43 ticks, discovered by Mike Playle on 25 April 2013 using a search utility he wrote called {Bellman}. Compare {boojum reflector}.  Four common Snark variants are shown below -- Playle’s original (top), and variants by Heinrich Koenig, Simon Ekström, and Shannon Omick (left, bottom, and right, respectively):

   .............................oo....................
   ............................o.o....................
   ......................oo....o......................
   ....................o..o..oo.oooo..................
   ....................oo.o.o.o.o..o..................
   .......................o.o.o.o.....................
   .......................o.o.oo......................
   ........................o..........................
   ...................................................
   .....................................oo............
   ............................oo.......o.............
   ............................oo.....o.o.............
   .........o.........................oo..............
   .........ooo.......................................
   ............o........o.............................
   ...........oo.......o..............................
   ....................ooo............................
   ...................................................
   ...oo..............................................
   ...o.....................oo........................
   oo.o......................o........................
   o..ooo....oo...........ooo.........................
   .oo...o...oo...........o......................o....
   ...oooo.....................oo..............ooooo..
   ...o...............oo........o.............o.....o.
   ....ooo............o.o.......o.o............ooo..o.
   .......o.............o........oo...............o.oo
   ..ooooo..............oo.....................oooo..o
   .o..o......................o...........oo...o...oo.
   .oo......................ooo...........oo....ooo...
   ........................o......................o...
   ........................oo.....................o.oo
   ..............................................oo.oo
   ...................................................
   ...................................................
   ......................................oo...........
   ......................................o............
   .......................................ooo.........
   ..............oo.........................o.........
   .............o.o.....oo............................
   .............o.......oo............................
   ............oo.....................................
   ...................................................
   ..........................o........................
   ................oo....oo.o.o.......................
   ...............o..o..o.o.o.o.......................
   ................oo...o.o.o.oo......................
   ..................oooo.oo..o.......................
   ..................o...o....o.......................
   ...................o..o.ooo........................
   ....................o.o.o..........................
   .....................o.............................

:SODGame:  {Seeds of Destruction Game}

:space nonfiller:  Any pattern that expands indefinitely to affect every cell in the Life plane, but leaves an expanding region of {vacuum} at its center.  Compare {spacefiller}; see also {antstretcher}.  The first nonfiller was discovered by Jason Summers on 14 April 1999:

    ...................ooo...............
    ..................o..o...............
    ............ooo......o....ooo........
    ............o..o.o...o....o..o.......
    ............o..o.o...o....o..o.......
    ..........o..........o..o.o.ooo......
    ..........oo..oo..o.o....o.....o.....
    ........o................oo..ooo.....
    ........ooo.o.oo..........o......o...
    ......o........o.........o.o...ooo...
    ......ooo.....o..........o........o..
    ...o.o.........................o.ooo.
    ..ooooo.o..........................o.
    .oo......o.....................ooooo.
    oo....oo..................o.o........
    .o.o...o..o...............o..o...o.o.
    ........o.o..................oo....oo
    .ooooo.....................o......oo.
    .o..........................o.ooooo..
    .ooo.o.........................o.o...
    ..o........o..........o.....ooo......
    ...ooo...o.o.........o........o......
    ...o......o..........oo.o.ooo........
    .....ooo..oo................o........
    .....o.....o....o.o..oo..oo..........
    ......ooo.o.o..o..........o..........
    .......o..o....o...o.o..o............
    .......o..o....o...o.o..o............
    ........ooo....o......ooo............
    ...............o..o..................
    ...............ooo...................

:spaceship: +add more links to new spaceships.  TBD

:Sparse Life:  TBD

:Spartan:  %Any pattern composed of subunits that can be easily constructed by {salvo}s. These may include {block}s, {blinker}s, {tub}s, {boat}s, {hive}s, {ship}s, {loaf}s, {eater 1}, {long boat}s, {pond}s, {toad}s and {beacon}s. Most {self-constructing} patterns are Spartan or mostly Spartan, to simplify the process of self-construction.%
:still life: +add {Spartan} link somewhere.  TBD.

:step: +... or {tick}

:superlinear growth: %Any pattern whose population asymptotically grows faster than any linear-growth pattern.% (applies to population growth, e.g., for {breeders} and {spacefillers}, and also to the reproduction rate of a {replicator}.  Due to limits enforced by the {speed of light}, no finite pattern can grow at a rate faster than quadratic.)

:swimmer lane:  See {bobsled}.

:switch-engine ping-pong: A very large (210515×183739) {quadratic growth} pattern found by Michael Simkin in October 2014, currently the smallest known %with just 23 on cells.%

:syringe:  A small stable glider-to-Herschel converter found by Tanner Jacobi on 19 March 2015.  the fastest safe {repeat time} is 78, but %it can be {overclocked}% at a following distance of 74 or 75 ticks.

:toggle circuit:  Any signal-processing {circuit} that switches back and forth between two possible states or outputs .  An example is the following alternating H-to-G {converter}:
   ...TBD

:toggleable gun:  %Any {gun} that can be switched on or off with an external signal%.

Example by Dean Hickerson, September 4, 1996:

    ..............oo..............o..
    ..............o.o.............o.o
    ..............o...............oo.
    .................................
    .................................
    .................................
    .................................
    ...............o..o....b.........
    .oooo..............o..b..........
    o...o..........o...o..bbb........
    ....o...........oooo.............
    o..o........................aaa..
    ............................a....
    .............................a...

In the figure above, glider B and an LWSS are about to send a glider NW.  Glider A will delete the next glider after B, turning off the output stream.  But if the device were already off, B wouldn't be present and A would instead delete the leading LWSS, turning the device back on.

:transparent lane:  A path through a signal-producing {circuit} that can be used to merge signal streams.  The signal -- usually a {standard spaceship} such as a {glider} -- can either be produced by the circuit, or it can come from elsewhere, passing safely through on the transparent lane without interacting with the circuit.

:TOLLCASS: Acronym for {The Online Life-Like CA Soup Search}.

:The Online Life-Like CA Soup Search:  A distributed search effort set up by Nathaniel Johnston in 2009, using a Python script running in {Golly}.  Results included a collection of the longest-lived 20x20 soups, as well as a census of over 174 billion {ash} objects.  %It has since been superseded by% {Catagolue}.

:track: +the active {signal} object

:trigger:  TBD.

:universal computer: ... that is known to be universal.

In 2009 Adam P. Goucher constructed a programmable {Spartan} universal computer/constructor pattern using stable {Herschel} circuitry.  TBD (included a minimal {single-arm}  universal constructor as well).

:universal constructor: + It *_is_* likely that it could be programmed to be construct itself,
Progressively smaller universal-constructor mechanisms have been used in the {linear propagator}, {spiral growth} pattern and the {Demonoid}s.

+Another strange consequence of the existence of universal constructors was pointed out by Adam P. Goucher in 2015.  Any glider-constructible pattern, no matter how large, can be constructed with a fixed number of gliders, probably less than ten thousand.  This can be done by working out a construction recipe for some type of {sliding block memory} with a faraway block, attached to a universal constructor.  The block’s position encodes an integer value that can be processed to retrieve as many bits of information as are needed to build a :1G seed:.  Eventually, after a completely unreasonable number of ticks, the seed can be {trigger}ed to produce the glider salvos which interact to construct the actual object.

:true: +update list of true-period guns.

:UC:  See {universal constructor}.

:universal toolkit:  A set of Life reactions and mechanisms that can be used to construct any object that can be constructed by glider collisions.

:waterbear:  an oblique spaceship discovered by Brett Berger on December 28, 2014. It is the smallest known oblique spaceship in terms of bounding box, superseding the {Parallel HBK}. It is currently the fastest oblique spaceship in Conway's Game of Life by several orders of magnitude.  Previous oblique spaceships, the {Gemini} and the {half-baked knightship}s, are stationary throughout almost all of their life cycles, as they construct the necessary mechanisms to support a sudden short move.  The waterbear constructs support for {(23,5)c/79} reactions which are in constant motion.

:wave:  TBD

:wavestretcher:  TBD

zweiback:  + could show a pattern using Scot Ellison’s HW volcano:

x = 41, y = 25, rule = B3/S23
10bo$8b5o17bo$7bo5bo14b5o$7bo2b2obo13bo5bo$3bob3obobob2o12bob2o2bo$3b
2o4bo16b2obobob3obo$6b2ob2o20bo4b2o$b5obobo2bo17b2ob2o$o6bo3bobo14bo2b
obob5o$2o2b5ob2obo13bobo3bo6bo$12b2o13bob2ob5o2b2o$5b2o4b3o13b2o$5b2o
4b3o5b2o6b3o4b2o$12b2o4bo2bo5b3o4b2o$2o2b5ob2obo5bobo5b2o$o6bo3bobo6bo
6bob2ob5o2b2o$b5obobo2bo14bobo3bo6bo$6b2ob2o17bo2bobob5o$3b2o4bo20b2ob
2o$3bob3obobob2o16bo4b2o$7bo2b2obo12b2obobob3obo$7bo5bo13bob2o2bo$8b5o
14bo5bo$10bo17b5o$30bo!
"What's purple and commutes?
The Evanston Express."
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Re: Life Lexicon update

Postby codeholic » March 30th, 2016, 12:57 am

:Herschel climber: The following glider-supported reaction used in the {waterbear}, which can be repeated every 79 ticks, moving the Herschel 23 cells to the right and 5 cells upward, and releasing two gliders to the northwest and southwest:

That is not the only Herschel climber.

EDIT: Another example:
x = 27, y = 96, rule = B3/S23
25bo$24bobo$24bobo$25bo18$19bo$18bobo$18bobo$19bo18$13bo$12bobo$12bobo
$13bo18$7bo$6bobo$6bobo$7bo18$bo$obo$obo$bo6$2b3o$3bo$3b3o!
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Re: Life Lexicon update

Postby dvgrn » March 30th, 2016, 1:29 am

codeholic wrote:
:Herschel climber: The following glider-supported reaction used in the {waterbear}, which can be repeated every 79 ticks, moving the Herschel 23 cells to the right and 5 cells upward, and releasing two gliders to the northwest and southwest:

That is not the only Herschel climber.

EDIT: Another example...

So that's a (6,21) offset instead of (7,23)? But it leaves behind pairs of blocks instead of beehives -- is it reburnable?

I guess my first thought is that other Herschel-climber reactions haven't been used in a completed spaceship yet, and they will become notable at that point. What would you suggest needs to be mentioned now under "Herschel climber" in the Lexicon?

I put in a separate definition for :Herschel-pair climber:, for the Centipede 31c/240 base reaction.
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Re: Life Lexicon update

Postby dvgrn » March 30th, 2016, 1:45 am

thunk wrote:Part 3 (apologies for the serial posting, I couldn't get under the character limit otherwise)...

This all looks great -- definitely no apologies needed. You could also do a ZIP attachment, if this kind of thing comes up again.

I'll run through all the %-delimited text when I get a chance, probably later this week, and add everything I agree with (which looks like it will be most of it).

Code: Select all
# gliders guaranteed to be all different from the previous set of 256
# -- they're all different parities, even...
x = 742, y = 617, rule = B3/S23
736bo$736bobo$736b2o8$731bo$731bobo$731b2o8$726bo$726bobo$726b2o8$721b
o$721bobo$721b2o8$716bo$716bobo$716b2o8$681bo29bo$681bobo27bobo$681b2o
28b2o8$676bo29bo$676bobo27bobo$676b2o28b2o8$671bo29bo$671bobo27bobo$
671b2o28b2o8$666bo$666bobo$666b2o3$696bo$696bobo$696b2o3$661bo$661bobo
$661b2o3$691bo$691bobo$691b2o$2bo$obo$b2o653bo$656bobo$656b2o$12bo$10b
obo$11b2o3$22bo$20bobo$21b2o628bo$651bobo$651b2o$32bo$30bobo$31b2o5$
616bo29bo$616bobo27bobo$616b2o28b2o13$596bo44bo$596bobo42bobo$596b2o
43b2o8$611bo24bo$611bobo22bobo$611b2o23b2o3$576bo$576bobo$576b2o3$591b
o14bo$591bobo12bobo$591b2o13b2o8$556bo$556bobo$556b2o$42bo4bo4bo4bo4bo
4bo4bo4bo4bo4bo4bo$40bobo2bobo2bobo2bobo2bobo2bobo2bobo2bobo2bobo2bobo
2bobo$41b2o3b2o3b2o3b2o3b2o3b2o3b2o3b2o3b2o3b2o3b2o478bo$571bobo$571b
2o$102bo$100bobo$101b2o483bo$586bobo$586b2o$112bo$110bobo$111b2o3$122b
o$120bobo$121b2o413bo14bo$536bobo12bobo$536b2o13b2o$132bo$130bobo$131b
2o433bo$566bobo$566b2o3$511bo19bo$511bobo17bobo$511b2o18b2o8$546bo$
546bobo$546b2o3$496bo$496bobo$496b2o8$526bo$443bo82bobo$442bo83b2o$
442b3o$284bo$285bo195bo$283b3o195bobo$481b2o3$506bo$438bo67bobo$437bo
68b2o$437b3o$289bo$290bo200bo$288b3o200bobo$491b2o3$466bo9bo$433bo32bo
bo7bobo$432bo33b2o8b2o$147bo4bo4bo4bo4bo4bo4bo4bo4bo4bo4bo234b3o$145bo
bo2bobo2bobo2bobo2bobo2bobo2bobo2bobo2bobo2bobo2bobo96bo$146b2o3b2o3b
2o3b2o3b2o3b2o3b2o3b2o3b2o3b2o3b2o97bo$293b3o5$428bo$427bo$427b3o$299b
o$300bo$298b3o5$328bo$327bo$327b3o$209bo$210bo$208b3o117bo$327bo$327b
3o$219bo$220bo$218b3o107bo$327bo$327b3o$229bo$230bo$228b3o107bo$337bo$
337b3o$249bo$250bo$248b3o87bo$337bo$337b3o$259bo$260bo$258b3o77bo$337b
o$337b3o$269bo$270bo$268b3o67bo$337bo$337b3o$279bo$280bo$278b3o72bo$
352bo$352b3o$304bo$305bo$303b3o52bo$357bo$357b3o$319bo$320bo$318b3o37b
o$357bo$357b3o$329bo$330bo$328b3o42bo$372bo$372b3o$354bo$355bo$353b3o
17$265b3o$265bo$266bo$256b3o$258bo$257bo32b3o$290bo$291bo$271b3o$273bo
$272bo52b3o$325bo$326bo$296b3o$298bo$297bo47b3o$345bo$346bo$306b3o$
308bo$307bo47b3o$355bo$356bo$306b3o$308bo$307bo67b3o$375bo$376bo$316b
3o$199b2o117bo$198bobo116bo77b3o$200bo194bo$396bo$326b3o$328bo$327bo4$
194b2o$193bobo124b3o$195bo124bo$321bo$241b3o$243bo$242bo112b3o$355bo$
356bo$266b3o$189b2o77bo$188bobo76bo107b3o$190bo184bo$376bo$276b3o$278b
o$277bo127b3o$405bo$406bo$296b3o$184b2o112bo$183bobo111bo122b3o$185bo
234bo$421bo$301b3o$303bo$302bo4$179b2o$178bobo164b3o$180bo164bo$346bo$
216b3o$218bo$217bo147b3o$365bo$366bo$226b3o$174b2o52bo$173bobo51bo147b
3o$175bo199bo$376bo$226b3o$134b2o92bo$133bobo91bo157b3o$135bo249bo$
386bo$226b3o$124b2o43b2o57bo$123bobo42bobo56bo167b3o$125bo44bo224bo$
396bo$226b3o$114b2o112bo$113bobo111bo187b3o$115bo299bo$416bo$236b3o$
104b2o58b2o72bo$103bobo57bobo71bo207b3o$105bo59bo279bo$446bo$256b3o$
94b2o162bo$93bobo161bo202b3o$95bo364bo8b2o$461bo7bobo$261b3o205bo$159b
2o102bo$158bobo101bo$160bo323b2o$484bobo$484bo$89b2o$88bobo294b3o$90bo
294bo93b2o18b2o$386bo92bobo17bobo$176b3o300bo19bo$154b2o22bo$153bobo
21bo222b3o$155bo244bo113b2o$401bo112bobo$181b3o330bo$84b2o97bo$83bobo
96bo242b3o$85bo339bo$426bo$196b3o$149b2o47bo$148bobo46bo247b3o$150bo
294bo48b2o$446bo47bobo$206b3o285bo$79b2o127bo$78bobo126bo267b3o$80bo
394bo$476bo$226b3o$228bo$227bo262b3o$490bo43b2o3b2o$491bo42bobo2bobo$
231b3o300bo4bo$74b2o157bo$73bobo156bo$75bo433b2o$509bobo$509bo2$415b3o
$415bo143b2o$416bo142bobo$146b3o410bo$69b2o77bo$68bobo76bo282b3o$70bo
359bo98b2o$431bo97bobo$151b3o375bo$34b2o117bo$33bobo116bo302b3o$35bo
419bo98b2o$456bo97bobo$166b3o385bo$24b2o38b2o102bo$23bobo37bobo101bo
307b3o$25bo39bo409bo103b2o$476bo102bobo$176b3o400bo$14b2o162bo$13bobo
161bo327b3o$15bo489bo43b2o$506bo42bobo$196b3o350bo$4b2o53b2o137bo$3bob
o52bobo136bo322b3o$5bo54bo459bo53b2o$521bo52bobo$201b3o370bo$203bo$
202bo$599b2o$599bobo$599bo$54b2o$53bobo389b3o$55bo389bo123b2o$446bo
122bobo$116b3o450bo$118bo$117bo347b3o$465bo128b2o$466bo127bobo$126b3o
465bo$49b2o77bo$48bobo76bo347b3o$50bo424bo143b2o$476bo142bobo$126b3o
490bo$128bo$127bo357b3o$485bo103b2o$486bo102bobo$126b3o460bo$44b2o82bo
$43bobo81bo367b3o$45bo449bo$496bo$126b3o$128bo$127bo377b3o$505bo103b2o
3b2o$506bo102bobo2bobo$126b3o480bo4bo$128bo$127bo392b3o$520bo$521bo$
131b3o$133bo$132bo417b3o$550bo$551bo$151b3o$153bo$152bo412b3o$565bo83b
2o3b2o3b2o3b2o3b2o3b2o3b2o3b2o$566bo82bobo2bobo2bobo2bobo2bobo2bobo2bo
bo2bobo$156b3o490bo4bo4bo4bo4bo4bo4bo4bo$158bo$157bo$639b2o3b2o$639bob
o2bobo$639bo4bo43$704b2o3b2o3b2o3b2o3b2o3b2o3b2o3b2o$704bobo2bobo2bobo
2bobo2bobo2bobo2bobo2bobo$704bo4bo4bo4bo4bo4bo4bo4bo3$694b2o3b2o$694bo
bo2bobo$694bo4bo!
[[ THUMBNAIL AUTOSTART STEP 10 THEME 5 ZOOM 2 X -50 LOOP 4096 ]]
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Re: Life Lexicon update

Postby codeholic » March 30th, 2016, 1:52 am

dvgrn wrote:I guess my first thought is that other Herschel-climber reactions haven't been used in a completed spaceship yet, and they will become notable at that point.

They might be not yet notable, but interesting enough to research them, and as a consequence they need a handle. I wouldn't reserve that name only for one certain reaction.
dvgrn wrote:What would you suggest needs to be mentioned now under "Herschel climber" in the Lexicon?

:Herschel climber: A high-{period} {fuse} that burns by means of a {Herschel} interacting with a small object, such as a {still life}, an {oscillator} or a {glider} and reproducing at an offset, just in place to interact with the next object in a series. Climbers that produce {reburnable} {debris} are the most interesting, as they can power {macro-spaceship}s and other contraptions moving at unusual {speed}s.

For instance, the following glider-supported (23,5)c/79 reaction emitting two gliders to the northwest and southwest was used in the {waterbear}:[...]

And by the way, the (23,5)c/79 reaction mentioned can be powered also with loaves, hives and boats, and that property is an integral part of the waterbear as well.

EDIT: And maybe it makes sense to move the most of the definition to a separate "climber" article, because of pi climbers (17c/45 in particular), b-heptomino climbers ((13,1)c/31 in particular) and so on.
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Re: Life Lexicon update

Postby dvgrn » March 30th, 2016, 2:02 am

codeholic wrote:They might be not yet notable, but interesting enough to research them, and as a consequence they need a handle. I wouldn't reserve that name only for one certain reaction...
And by the way, the (23,5)c/79 reaction mentioned can be powered also with loaves, hives and boats, and that property is an integral part of the waterbear as well.

Sounds good. As I recall, there are other Lexicon definitions that read something like "Any {general description of reaction}. May be used to refer to {classic specific case}." Maybe I'll add a sentence along those lines. Thanks again!
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Re: Life Lexicon update

Postby dvgrn » April 5th, 2016, 11:12 pm

Okay, time for another status update on the Life Lexicon project.

I've gone through and integrated thunk's suggestions into my own notes on new definitions to be added, and current definitions to be updated.

Looks like the new material has grown to over half the size of the original Life Lexicon text file already -- in kilobytes, anyway. Unfortunately I don't think it's because I've collected over half as many definitions as the current Lexicon... I'm a bit worried that I'm just not as good at being concise. Probably using too many words, or too many long words, or something.

However, I'm hoping that it's mostly just that I'm quoting more small patterns -- bigger than the old average pattern size, for sure, but still smaller than the old Life Lexicon limit of 64x64 (with one exception). That takes up quite a bit of space, but it seems worth it; the pattern pictures are the best part. And there are quite a few things that didn't fit into 64x64 in 2007, but they do now!

I keep noticing commonly used terms that haven't gotten an entry yet, so I'm sure there's plenty more left to do. But this is getting to look like a good start, anyway.

So if you don't see a definition in the current Lexicon that's packaged with Golly, or in the attachment to this message, and if it seems like it's a really common term that everybody is using...

then please write a definition and post it here, because otherwise it might not show up in the Life Lexicon for another ten years.

Comments and suggestions welcome. As usual, I'll quite likely make changes, but also reserve the right to be stubborn based on arbitrary criteria of my own. Luckily it's always possible for you to make your own copy and finish the project properly yourself, if you really really want it to be done right...!
Attachments
lexicon-all-new-definitions-including-thunk's.txt
New and updated definitions for the Life Lexicon as of 5 April 2016.
(199.2 KiB) Downloaded 80 times
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Re: Life Lexicon update

Postby rowett » April 6th, 2016, 2:13 am

Excellent work!

I wrote a quick script to convert this to HTML and in doing so discovered some links that do not resolve. I had to modify the text slightly (it contained a few special characters and the last entry was missing a leading colon).

When you run the script it generates four files:
  • lexicon.html - a quick and dirty conversion of the lexicon.txt file. Converts :glider: to anchor targets and {glider} to an anchor.
  • targets.txt - a list of :targets: found in the lexicon, one per line
  • anchors.txt - a list of {anchors} found in the lexicon, one per line
  • missing.txt - a sorted list of anchors with no targets
Attached are:
  • a zip file (webify.zip) containing the bash script (webify.sh)
  • the slightly modified lexicon (lexicon.txt)
  • the list of anchors with no targets (missing.txt)
The next version of the script will allow the patterns to be displayed inline in LifeViewer in the generated HTML.
Attachments
webify.zip
(630 Bytes) Downloaded 68 times
missing.txt
(2.09 KiB) Downloaded 70 times
lexicon.txt
(199.21 KiB) Downloaded 84 times
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Re: Life Lexicon update

Postby dvgrn » April 6th, 2016, 6:38 am

rowett wrote:I wrote a quick script to convert this to HTML and in doing so discovered some links that do not resolve. I had to modify the text slightly (it contained a few special characters and the last entry was missing a leading colon).

Thanks for getting started on the cleanup stage! The big missing piece is the original Life Lexicon -- the text I posted is only the new material, to make it easier to review. That accounts for all the missing links like {block} and {boat} and {B heptomino} and so on. Looks like most of the rest are accidental minor variants of terms that are already defined, but there will still be a few holes left to fill.

Stephen Silver's source distribution for the Life Lexicon (see "download source distribution" link) includes a similar bash script and several other cleanup scripts, none of which I have run yet. Here's the README summarizing the available tools:

This zip file contains the source of release 25 of the Life Lexicon,
a lexicon of terms used in Conway's Game of Life.

The source is unlikely to be of any use to most people, but is provided for
two reasons:
  (1) It will be of use to anyone who wishes to maintain the Lexicon in the
      future, should I for any reason cease to do so.
  (2) Some of it may be of use if anyone wants to convert the Lexicon into
      some other format.

The file supplied are:
    README        (this file)
    makehtml.sh   (a bash script to generate the HTML versions)
    htmlize.c     (C source for the `htmlize' program)
    perfect.c     (C source for the `perfect' program)
    head.htm      (the single-page HTML version of the introductory notes)
    tail.htm      (the single-page HTML version of the bibliography)
    ?.htm         (27 tiny files used for the multipage HTML version)
    top1.htm      (used at the top of the multipage HTML files)
    top2.htm      (also used at the top of the multipage HTML files)
    bot.htm       (used at the bottom of the multipage HTML files)
    lexicon.txt   (the ASCII version of the Lexicon)
    lexiconf.htm  (the frameset for the single-page HTML version)
    buttons.htm   (the button bar frame of the single-page HTML version)
    lex.htm       (the multipage HTML version of the introductory notes)
    lex_bib.htm   (the multipage HTML version of the bibliography)
    lifelex.el    (a Life Lexicon mode for Emacs)
    emacs.txt     (instructions for using lifelex.el)
    lifelex.css   (stylesheet for HTML versions)

The files htmlize.c and perfect.c should compile with any ANSI C compiler.

The main body of the ASCII version is converted into HTML by `htmlize',
which generates files for both the single-page and the multipage versions.
In addition, the `perfect' program is used to remove extraneous bytes from
from lexicon.txt and ensure that it uses tabs in the way `htmlize' expects.
Extra HTML needs to be added to the beginning and end of the files
generated by `htmlize'.  You should study the bash script makehtml.sh
to see the details of the process.

The new Lexicon entries aren't quite ready for prime time yet. Now that the new stuff is available as a separate file, the next step is to merge those entries into the original Lexicon in alphabetical order. I may write a throwaway script to do the merge for me. Might just do it manually, though, since that forces me to re-read each entry and gives me a better chance of catching mistakes.

Not all of the definitions are complete new entries. Some contain + and - characters, indicating material to be added or subtracted from the current Lexicon entry. In some cases Stephen Silver may have made changes to the 2007 draft, that may have to be merged with my 2016 notes. I usually worked from the 2007 draft, but probably slipped sometimes and looked things up in the published Lexicon.

In the attached two-part copy containing all definitions*, I decided to take out the line breaks in existing Life Lexicon entries -- crossing my fingers that I haven't broken any subtle formatting that I'll regret later. Generally an indent of eight spaces means a table or an ASCII pattern, five spaces means a new paragraph, and three spaces means a continuation of text after a pattern without a new paragraph. At the beginning and end of the original Lexicon there are sections that are still word-wrapped, where a two-space indent means a new paragraph.

I thought of adding line breaks to the new entries instead. A regexp replacement of "(?=.{73,})(?:(.{0,73})(?:\r\n?|\n\r?)|(.{0,73}))[ ]" with "\1\2\n " almost worked, but the first lines ended up slightly short. Anyway that seemed a little bit premature -- it's much easier to leave the line breaks off for now and add them at the last minute, after the inevitable final editing. Or Stephen Silver's cleanup code may put them in automatically, I haven't checked yet.

* I've run into a couple of spots where I remember having made changes, but they've mysteriously been reverted. Probably inevitable for this kind of project. Time to go check my backups.

rowett wrote:The next version of the script will allow the patterns to be displayed inline in LifeViewer in the generated HTML.

When I get all the add/remove notes merged -- i.e., a draft of the attached file that is all in one piece, in alphabetical order -- then I'll try to get Stephen Silver's original cleanup utilities running. Theoretically they should be able to produce correctly linked single-page and multipage HTML versions of the new Lexicon. If I recall correctly, they also produce a report equivalent to missing.txt.

-- Then I have to remember how to wrestle the result into a shape that Golly can use. The links are a little different. Won't run out of fun lexicographical headaches for a while yet...!
lexicon-dvgrn-thunk-rowett-nowrap.txt
All current and new Lexicon entries, with line breaks removed.
Also minor corrections in passing, e.g. to :AK94 gun:.
(538.83 KiB) Downloaded 71 times
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Re: Life Lexicon update

Postby dvgrn » April 6th, 2016, 7:22 am

Yup, the combined file yields a much more reasonable missing.txt when I run it through webify.sh:

revised missing.txt:
0hd Demonoid
10hd
10hd Demonoid
2c/3
9hd
AK-47
ambidextrous
B heptomino
block puller
Blockic
BRx46B
catalysts
ChrisCainSpartanLoafBoatBlocksHighwayRobberEaterConstellation
colour
conduits
constellation
construction arms
dependent conduits
double-barreled
dying spark
eaters
edge-shooter
elbow op
elbow operations
elementary conduits
figure-eight
fire
full diagonal
Ghost Herschel
glider constructible
glider lane
glider recipe
glider reflector
glider-constructible
half diagonal
Herschels
Hershel-to-glider
knightships
lanes
logic gate
monochromatic
novelty generating
oblique
one-arm
overclocked
Parallel HBK
Parallel HBK gun
period doubler
phases
pi heptomino
Pulsar
Push
queen-bee shuttle
R pentomino
reburnable
recipe
recipes
seeds
side spark
signal wires
signals
single-channel
slow salvos
slow-salvo
staged-recovery circuit
telegraph
ticks
toolkit
tracks
transparent
unit cell
universal
universal construction
universal constructors
wedge grow
welded

There's a fair amount of definition-writing to do here, but most of these really have definitions under slightly different names -- I made a lot of mistakes with plurals and verb forms, it looks like, so those will clean up quick. Stephen Silver's code correctly converts a link like {weld}ed into a link that says "welded" but points to the :weld: anchor. I think it handles capitalized variants better, too, so that cuts down the list a bit more.

Nobody should worry about defining or cleaning up anything on the revised missing.txt list, please. I'll get to it in the next few days, and post an alphabetized version in another week or three. If I created a bad link, I probably have a definition in mind and it will most likely just slow me down to merge someone else's fixes.

[For example, "ChrisCainSpartanLoafBoatBlocksHighwayRobberEaterConstellation" was just a placeholder, surprise surprise, that I forgot about -- the right term is "sidesnagger".]

Again, the most magnificently marvelous thing at this point would be the appearance of new definitions for commonly used terms that aren't mentioned in the latest attached file at all. My contributions have been heavily biased toward self-constructing-pattern terminology, because that's what I know best. People with other areas of expertise could help restore the balance.
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Re: Life Lexicon update

Postby Dean Hickerson » April 10th, 2016, 10:41 am

I noticed that the entry for 'volatility' is not up-to-date; Jason Summers found a statorless p3 in August 2012. As far as I know, it doesn't have a name, so it can't have its own entry in the lexicon. Is it OK to include the pattern in the entry for volatility? If so, then here's a suggested rewrite:

:volatility:  The volatility of an {oscillator} is the size (in cells) of its {rotor} divided by the sum of the sizes of its rotor and its {stator}.  In other words, it is the proportion of cells involved in the oscillator which actually oscillate.  For many periods there are known oscillators with volatility 1, see for example {Achim's p16}, {figure-8}, {Kok's galaxy}, {mazing}, {pentadecathlon}, {phoenix}, {relay}, {smiley} and {tumbler}.  Such an oscillator of period 3 was found in August 2012 by Jason Summers.
   .........*.*.....*...*.....*.*.
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   ****.**.***.........****.**.***
   ***.**.****.........***.**.****
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The smallest period for which the existence of such statorless oscillators is undecided is 5. There are oscillators with volatility arbitrarily close to 1 for all but finitely many periods, because of the possibility of feeding the gliders from a {true} period n {gun} into an {eater}.
     The term "volatility" is due to Robert Wainwright.  See also {strict volatility}.
Dean Hickerson
 
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Re: Life Lexicon update

Postby dvgrn » April 13th, 2016, 4:39 pm

Dean Hickerson wrote:I noticed that the entry for 'volatility' is not up-to-date; Jason Summers found a statorless p3 in August 2012. As far as I know, it doesn't have a name, so it can't have its own entry in the lexicon. Is it OK to include the pattern in the entry for volatility? If so, then here's a suggested rewrite...

Yes, this looks good -- thanks! In the original Lexicon there are quite a few patterns included as illustrations in these kinds of general terminology definitions. Often it's a good way to sneak in a nameless-but-interesting pattern.

The general policy I'm trying to follow is to keep definitions short and simple, with links to other relevant Lexicon entries -- not all possible information, necessarily -- that seems more like the LifeWiki's job these days, to collect all the historical details for example.

A picture is worth 2^10 words, though, so I try to come up with a small ASCII pattern if possible, under 64x64. If there's more than one pattern in a single definition, I try to think about whether it might actually be two definitions.

I'm not really good at the "short and simple" part, but I figure I can always delete words later...!
dvgrn
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