History Of ConwayLife

For general discussion about Conway's Game of Life.
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Yoel
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Re: History Of ConwayLife

Post by Yoel » December 9th, 2020, 8:38 am

Harry99 wrote:
December 9th, 2020, 5:35 am
I Want to know about the history of conway's game of life, Can Someone tell me the history of conway's game of life?
The is a nice introductory film by Rudy Rucker about cellular automata in general:

https://www.youtube.com/watch?v=lyZUzakG3bE

There are a plenty of good books on cellular automata. For the history of Conway's Game of Life in particular, just read LifeWiki and google for details. It was originally publicized in the October 1970 issue of Scientific American, in Martin Gardner's column "Mathematical Games". The first computer versions appeared in early 1970s. Lots of early stuff was actually discovered by playing manually on Go boards etc. I personally know someone who used to play it on a Scrabble board.

Watch it being played on PDP-7:

https://www.youtube.com/watch?v=hB78NXH77s4

Someone retroactively wrote an implementation for EDSAC (on a simulator), one of the first computers from 1949. You can check it out here:

https://www.dcs.warwick.ac.uk/~edsac/

The simulator runs on Linux/*nix under Wine. Of course, Conway's Game of Life was not discovered yet back then. Someone just did it for fun or for the simulator's testing. :-)

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Re: History Of ConwayLife

Post by Hunting » December 9th, 2020, 9:11 am

Harry99 wrote:
December 9th, 2020, 5:35 am
I Want to know about the history of conway's game of life, Can Someone tell me the history of conway's game of life?
Ah, sure! Dvgrn can probably provide a much better answer than me, but why not.

Conway's Game of Life is created by John Horton Conway in 1970 (with some early explorations with the R-pentomino in 1969), deriving from the concept of Cellular Automata from John von Neumann, who created a very complex circuitry cellular automaton with tons - I mean tens - of states.

Martin Gardner published Conway's Game of Life on Scientific American, and the game enjoyed a bit of fame and is secretly being investigated in several academic communities, such as universities. Lifeline was published in March 1971 till 1973.

Most of the investigation done during 1971-1980 are looking for oscillators, since they were relatively easy to find (and, because Conway's Game of Life is relatively new at that time, all kinds of random patterns and fuses and p2s and blah blah blah are notable. They're not now, and that explains the activity in the Other Cellular Automata forum, attempting to recreate the 1971-1980 period but with other "games of life".) In 1975, my father was born. The most important pattern discovered during this period is the queen bee shuttle (1970), which leads to the Gosper glider gun, still the representative of Conway's Game of Life to the world today, and the twin bee shuttle (1971), which leads to the bi-gun. Some XWSS-tagalongs was also created, a good representative of this party being ecologist (1971).

Dean Hickerson wrote the first ever search program for Conway's Game of Life, and found several new velocities, such as c/3. It led to a fair amount of spaceship technology, and that part of history is pretty much covered by David Bell's glorious six-part article ("Spaceships in Conway's Life" the download links).

Gosper glider gun based circuitry were used all the way until 1995 when David Buckingham, a hardcore Lifenthusiast known to like high-period oscillators, discovered that a certain methuselah called Herschel can be transported with still life "catalysts", without damaging the catalysts, effectively forming a wire. Period 58 and above oscillators can be obtained with such wires forming a loop, and it can, obviously, be used for technology. Gosper glider gun became less popular since then. The relevant histories were explained in this article.

...I have things to do now, will write later.

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Re: History Of ConwayLife

Post by dvgrn » December 9th, 2020, 9:35 am

I don't know about a better answer, but I can do longer easily enough.
Harry99 wrote:
December 9th, 2020, 5:35 am
I Want to know about the history of conway's game of life, Can Someone tell me the history of conway's game of life?
Here are a bunch of bullet points that I wrote up some time ago, so they're quick to copy/paste, with a few additions:

1970-2000:
  • John Conway and a group of graduate students and hangers-on started investigating the B3/S23 rule in late 1969, discovering for example the first glider escaping from an R-pentomino explosion. Conway rounded the date to 1970.
  • In October 1970, Martin Gardner published the first of three "Mathematical Games" columns about Conway's Life in Scientific American, and got an impressively large response from readers.
  • Bob Wainwright started a newsletter for Lifenthusiasts, LIFELINE, which collected and published new discoveries for several years in the early 1970s.
  • David Buckingham collected a lot of objects and produced a lot of magical glider syntheses of them, starting very early on.
  • Bob Wainwright was active through the mid-1980s or so, discovering strange new oscillators.
  • Achim Flammenkamp started a long tradition of soup searches in the late 1980's, which continues today with catagolue.appspot.com. That
    included finding "mold" and "jam" on loaves floating in his soups in 1989 (how did that take so long?)
  • Dean Hickerson put together a lot of mathematically-minded patterns in the 1980's and 1990's, particularly patterns with strange and
    interesting new growth rates.
  • Then a scattering of new but not glider-constructible spaceships appeared, one each in 1989 and 1991 I think, followed by a sudden
    flood of new spaceships in 1992. The 1992 appearance in the Lifenthusiast community of David Bell and his search program "lifesrc" was not a coincidence, and independent of that was a string of successively smaller Corderships constructed by Dean Hickerson.
  • The spaceship excitement was replaced by universal stable circuitry excitement in 1995/1996, with the appearance of David Buckingham's
    initial set of Herschel tracks and Paul Callahan's stable reflectors.
  • That got Dietrich Leithner interested for a few years. His burst of research started, among other things, the unbelievably time-consuming project of building a glider gun for every period between 14 and 1000. That collection didn't get finished until September 2003, and the optimization process continues to this day.
  • In the late 1990s Dean Hickerson started investigating weird signal-carrying circuits with a new 'drifter' search program. These are like embedding a little bit of a different universe into Conway's Life -- e.g., 2c/3 and 5c/9 wires, which break the B3/S23 speed limit for spaceships traveling through vacuum.
2000-2009:
  • 2001: This was when I showed up in the Lifenthusiast community, after being completely unaware of the progress in Life discoveries since I'd last heard about Life in the mid 1980s. I managed to put together a record smallest stable reflector, through sheer dumb luck and not knowing any better -- beginner's luck seems to be an important force in the Life universe.
  • 2002: Quite a few people got a lot of construction and optimization practice building glider guns, with the help of Karel Suhajda's Hersrch (Herschel search). The full collection, with an example of every period from 14 to 1000, was completed the next year.
  • 2003: Noam Elkies was able to find glider collisions that produced a new breed of spaceship, moving at two fifths of lightspeed orthogonally instead of the usual one half lightspeed. The 2c/5 ship itself was already well-known, of course: search programs had been working overtime since the early 1990s, so there was no shortage of known spaceships with various speeds -- thousands of them, or really an unbounded number unless you set a maximum bounding-box size. But it's a fact of Life that it's usually much easier to find a new spaceship than to find a way to build it out of colliding gliders. Nobody had managed to find a new spaceship recipe for decades.
    Now suddenly it was possible to build a "factory" for a 2c/5 ship... an extraordinarily large and ungainly one, but perfectly reliable. A number of the biggest silliest patterns in this time period were my fault, like a couple of Cordership guns also from 2003 -- and also huge and awkward, but it was still kind of fun to watch them work. The predictable ants'-nest of activity was mesmerizing in a way similar to those mechanisms you see in science museums sometimes for running marbles around on improbably complicated tracks.
  • 2004: Gabriel Nivasch completed a truly enormous spaceship, the Caterpillar, based on earlier collaborative work by several other Life List people. Almost the only comparably large and complicated object that has been constructed since then is the 0E0P metacell... which was also a solo effort, putting together lots of pieces created by lots of other people. There's something of a pattern here (no pun intended).
  • 2005: Golly's HashLife algorithm suddenly made it much less painful to simulate very large patterns (like the Caterpillar).
  • 2007: Noam Elkies again, another glider-synthesis first, finding a way to synchronize several gliders to feed a spark of Life into the end of a 2c/3 signal wire. Then the problem was again to start with a single signal and produce all those synchronized gliders -- and the solution again was a Brobdingnagian stable circuit (see Scripts/Python/heisenburp.py in Golly).
  • 2008: People in the post-Golly like Brice Due, Jason Summers, and (especially) Adam P. Goucher cheerfully dispensed with the idea that patterns needed to be anything like a reasonable size ... and so they industriously put together the biggest construction developments of the time period: Turing Machines, Universal Register Machines, patterns with O(sqrt(log(t))) growth, universal computer-constructors, a couple of metapixel-metacells, and computers for calculating phi and pi and printing them out as patterns of blocks.
2010-2019:
  • 2010: Gemini spaceship! Out of the blue, Andrew D. Wade posted a completed self-constructing spaceship -- something that people had been talking about for decades, but nobody thought was remotely within reach.
  • 2013: after a series of slow improvements to the Gemini's technology came, the linear propagator finally showed up. Either this was the first true self-replicating pattern in the Game of Life... or it didn't really count, because only one copy of the pattern is ever active at a time. I'm inclined to say it didn't quite count.
  • 2014-present: glider syntheses of spaceships. New tools appeared, and new experts with new construction techniques -- particularly
    Extrementhusiast, who had a hand in a majority of the dozen or more recipes for never-before-synthesizable spaceships that showed up starting in 2014.
  • 2014-present: self-supporting spaceships (half-baked knightship, waterbear, Centipede, Caterloopillar). The name "Caterloopillar" is something of a tribute to Douglas Hofstadter's "strange loop" concept. It's a deeply weird Life spaceship design where each half of the spaceship builds the other half as the whole thing is flying along, reminiscent of Escher's "Drawing Hands" lithograph.
  • 2015-2017: glider syntheses of still lifes. All that practice crashing gliders together paid off, and recipes were completed showing that all N-cell still lifes could be constructed using less than N gliders, for N up to 16. There are 3,286 different 16-bit still lifes, and without considerable training most people -- and even most Lifenthusiasts -- would be unable to come up with a way to crash gliders together to produce even one of them. So this was a fairly monumental task to complete, even with Mark Niemiec's expert system to take care of all the easy cases.
  • 2015-present: self-constructing spaceships (Demonoid, Orthogonoid, loopship, camelship). These were all made possible due to a "single-channel" construction breakthrough made by simeks in December 2015. It's one of the key developments that made the 0E0P metacell even vaguely possible.
  • 2018: proof of constructability of any glider-constructible pattern no matter how large, using a fixed number of gliders recently reduced to 17. See Reverse caber tosser. This seems even more difficult to believe in than Conway's and Gosper's groups' original proofs of the existence of replicators and many other universal-constructor-based UPHOs (Unbuildable but Provable Huge Objects) (not a real Life acronym.)
    But it turns out you only need 17 gliders to build anything, even a fleet of a million Caterpillars, or the complete works of Shakespeare spelled out in the Life universe as arrangements of blocks in Helvetica 100-point font. You just have to be willing to put some of the gliders really really far away, and encode all the gazillion bits of required construction information in the size of the space between the two groups of gliders.
  • 2018: Adam P. Goucher's 0E0P metacell -- an impressive "first" in an impressive number of different categories... and yet it's too huge for current computer hardware to actually simulate it in any satisfactory way. Give Moore's Law a few more decades and *maybe* this pattern will be a little easier to handle.
  • 2019-2020: New unexpected things like the doo-dah attachment to the weekender keep showing up, as Moore's Law keeps making the available search space a little bigger... and new beginners keep showing up to try their beginner's luck!
There are a lot more categories and sub-specialties out there. I probably tend to go on more about the topics that I'm particularly
interested in, of course. So it goes. A lot the rest is out there in the annual Category pages on the LifeWiki.

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Re: History Of ConwayLife

Post by MathAndCode » December 9th, 2020, 12:25 pm

dvgrn wrote:
December 9th, 2020, 9:35 am
[*] 2001: This was when I showed up in the Lifenthusiast community, after being completely unaware of the progress in Life discoveries since I'd last heard about Life in the mid 1980s. I managed to put together a record smallest stable reflector, through sheer dumb luck and not knowing any better
Did the first way that you found to send a glider back delete the beehive cleanly, or did you find at least one method that didn't work before that particular arrangement of two blocks, a tub, a fishhook, and an eater 2? (I'm wondering about the possibility of other boojum shuttles similar to this one.)
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Re: History Of ConwayLife

Post by dvgrn » December 9th, 2020, 1:08 pm

MathAndCode wrote:
December 9th, 2020, 12:25 pm
dvgrn wrote:
December 9th, 2020, 9:35 am
[*] 2001: This was when I showed up in the Lifenthusiast community, after being completely unaware of the progress in Life discoveries since I'd last heard about Life in the mid 1980s. I managed to put together a record smallest stable reflector, through sheer dumb luck and not knowing any better
Did the first way that you found to send a glider back delete the beehive cleanly, or did you find at least one method that didn't work before that particular arrangement of two blocks, a tub, a fishhook, and an eater 2? (I'm wondering about the possibility of other boojum shuttles similar to this one.)
It was really pretty much the first thing that showed up. I was trying single catalysts by hand on a truncated copy of Paul Callahan's Herschel receiver, and happened to try putting a block here (green):

Code: Select all

x = 26, y = 36, rule = LifeHistory
18.C$16.3C$15.C$15.2C2$2.A$3.A$.3A2$25.C$23.3C$22.C$22.2C$2C$2C6$12.
2C$12.2C13$20.2A$20.2A!
#C [[ AUTOSTART STOP 240 ]]
#C [[ Z 10 T 218 T 219 "(Great Jumping Hornswoggles,\nwhat just happened there?)" ]]
So the next two weeks of late nights combing through thousands of 'catalyst' search results were all just various attempts to find a catalysis that would drop that block back in the correct location.

If I had known how improbable it was that such an arrangement of (Spartan-ish) catalysts even existed, I might not have tried for so long. There weren't nearly as many known options for catalysts in 2001.

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Re: History Of ConwayLife

Post by MathAndCode » December 9th, 2020, 1:28 pm

dvgrn wrote:
December 9th, 2020, 1:08 pm
It was really pretty much the first thing that showed up. I was trying single catalysts by hand on a truncated copy of Paul Callahan's Herschel receiver, and happened to try putting a block here (green):
That's interesting how you were able to reuse part of the mechanism. I wonder whether the beehive can be converted into a pi or R sequence instead of simply being deleted. Obviously, the glider would have to come from a different direction in order for the output to be accessible.



Edit: Can the fishhook be replaced?

Code: Select all

x = 49, y = 33, rule = Conway's Life
obo$b2o7b2o$bo8b2o3$44b2o$45bo$44bo$44b2o$6bo28b2o$4bobo3b2o23bobo$5b
2o2bo2bo23bo$10b2o$17b2o$17b2o28b2o$47b2o6$4b2o$4b2o$8b2o$7bobo22b2o$
7bo24bo$6b2o25b3o$19b2o14bo$19b2o3$21b2o$21b2o!


Another edit: Here's another example.

Code: Select all

x = 49, y = 33, rule = Conway's Life
obo$b2o7b2o$bo8b2o3$44b2o$45bo$44bo$44b2o$6bo28b2o$4bobo3b2o23bobo$5b
2o2bo2bo23bo$10b2o$17b2o$17b2o28b2o$47b2o6$4b2o$4b2o$8b2o24b2o$7bobo24b
obo$7bo28bo$6b2o23b2o3b2o$19b2o10b2o$19b2o3$21b2o$21b2o!
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Re: History Of ConwayLife

Post by praosylen » December 9th, 2020, 4:56 pm

MathAndCode wrote:
December 9th, 2020, 1:28 pm
Can the fishhook be replaced?
Here's a hint from someone who has been working with stable conduits for several years: generally if you find yourself asking this question, you're most likely hopelessly on the wrong track with whatever you're doing. The answer is probably "yes" with enough effort and glider synchronization, but in practice nothing that ever requires replacing a bait object rarer than something like a block or a beehive (or sometimes a boat or a loaf) is worth the effort to finish outside of something spectacular like an XWSS output or a fast or Spartan G-to-X — and it had better be something truly spectacular if the object you're trying to salvage is eater-level uncommon.... All in all, while I admire your faith, I doubt you'll be getting many takers to help you try to complete these kinds of reactions, since in most of our experience, they're usually more trouble than they're worth just to create things that are usually for all practical purposes just (large and often high-repeat-time) curiosities.
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Re: History Of ConwayLife

Post by MathAndCode » December 9th, 2020, 5:27 pm

A for awesome wrote:
December 9th, 2020, 4:56 pm
MathAndCode wrote:
December 9th, 2020, 1:28 pm
Can the fishhook be replaced?
Here's a hint from someone who has been working with stable conduits for several years: generally if you find yourself asking this question, you're most likely hopelessly on the wrong track with whatever you're doing. The answer is probably "yes" with enough effort and glider synchronization, but in practice nothing that ever requires replacing a bait object rarer than something like a block or a beehive (or sometimes a boat or a loaf) is worth the effort to finish outside of something spectacular like an XWSS output or a fast or Spartan G-to-X — and it had better be something truly spectacular if the object you're trying to salvage is eater-level uncommon.... All in all, while I admire your faith, I doubt you'll be getting many takers to help you try to complete these kinds of reactions, since in most of our experience, they're usually more trouble than they're worth just to create things that are usually for all practical purposes just (large and often high-repeat-time) curiosities.
I think that you're confused about what I'm trying to do. I want to replace the fishhook with a permanent reaction, not find a reaction that restores the fishhook as a transparent catalyst. However, there are more common objects that could theoretically work as transparent catalysts.

Code: Select all

x = 49, y = 33, rule = Conway's Life
obo$b2o7b2o$bo8b2o3$44b2o$45bo$44bo$44b2o$6bo28b2o$4bobo3b2o23bobo$5b
2o2bo2bo23bo$10b2o$17b2o$17b2o28b2o$47b2o6$4b2o$4b2o$8b2o$7bobo22b2o$
7bo23bobo$6b2o23b2o$19b2o$19b2o3$21b2o$21b2o!

Code: Select all

x = 49, y = 33, rule = Conway's Life
obo$b2o7b2o$bo8b2o3$44b2o$45bo$44bo$44b2o$6bo28b2o$4bobo3b2o23bobo$5b
2o2bo2bo23bo$10b2o$17b2o$17b2o28b2o$47b2o6$4b2o$4b2o$8b2o24b2o$7bobo24b
2o$7bo$6b2o$19b2o$19b2o3$21b2o$21b2o!
The reason that I used fishhooks instead of blocks or other objects is because I wanted to indicate that I want a permanent catalyst, not a transparent or sacrificial object. Is it not being interpreted that way? If not, how should I better indicate my intentions?
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Re: History Of ConwayLife

Post by praosylen » December 9th, 2020, 5:31 pm

MathAndCode wrote:
December 9th, 2020, 5:27 pm
I want to replace the fishhook with a permanent reaction, not find a reaction that restores the fishhook as a transparent catalyst.
Okay, that makes a lot more sense. I've seen a lot of "can this eater be restored" types of posts recently so I guess I just assumed. Sorry about that!
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Re: History Of ConwayLife

Post by MathAndCode » December 9th, 2020, 6:53 pm

A for awesome wrote:
December 9th, 2020, 5:31 pm
Okay, that makes a lot more sense. I've seen a lot of "can this eater be restored" types of posts recently so I guess I just assumed. Sorry about that!
Replacing a fishhook isn't completely unfeasible, but chances are that it is not worth the large size and long repeat time necessary to either synchronize two gliders for a synthesis, search for a transparent reaction, or find a reaction that creates a fishhook, clean it up, and attach the input. There are some ways to make or restore a fishhook, but their scarcity proves the general rule. Here is a transparent fishhook reaction that I'm sure was found by a Bellman search for transparent catalysts in general, and here is a slight modification of a reaction that I found when I was trying to do something else with a century (My best guess is that I was trying to get an I-sequence with some junk behind it because I had found an I→C that left a beehive behind (I think that it could have theoretically been removed with a stable catalyst, but that would have made inserting the I-sequence very awkward.), and wanted a way to make an I-sequence with some trailing junk that would annihilate the beehive.), wanted to remove one of the blocks, and tried a fishhook.

Code: Select all

x = 19, y = 16, rule = Conway's Life
8b2o$8b2o$o16b2o$3o14bo$3bo11bobo$2b2o11b2o6$5bo$6bo$7bo$6bo$4b2o!
wwei23 realized that that block can be removed with a dot sparker in a way that works with any relative timing and therefore can be used in stable circuitry. I never found a way to make an I-sequence with appropriate junk behind it, though.
By the way, here are some more examples of partial conduits that can use a fishhook or something else as a sacrificial object but that I'd like to see using a permanent catalyst instead.

Code: Select all

x = 128, y = 47, rule = LifeHistory
7.D31.D31.D31.D$6.3D29.3D29.3D29.3D$8.2D30.2D30.2D30.2D17$2E$.E64.E30.
2E$.E.E30.2E29.E.E29.E.E$2.2E30.2E30.2E30.2E2$20.2A30.2A30.2A30.2A$19.
A.A29.A.A29.A.A29.A.A$20.A31.A31.A31.A9$14.C31.C31.C31.C$13.3C29.3C29.
3C29.3C$12.2C30.2C30.2C30.2C2$25.2A30.2A30.2A30.2A$25.2A30.2A30.2A30.
2A$25.2A30.2A30.2A30.2A$25.A31.A31.A31.A$12.2A10.A.A17.2A10.A.A17.2A10.
A.A17.2A10.A.A$12.2A11.A.A.3A12.2A11.A.A.3A12.2A11.A.A.3A12.2A11.A.A.
3A$26.A.4A26.A.4A26.A.4A26.A.4A$27.A31.A31.A31.A!

Code: Select all

x = 37, y = 37, rule = LifeHistory
6.2E$6.E28.E$4.E.E27.E.E$4.2E28.2E2$.2C28.2C$2C28.2C$.C29.C2$5.D29.D$
5.2D28.2D$4.2D28.2D14$7.E$5.3E27.2E$4.E29.E.E$4.2E28.2E2$.2C28.2C$2C28.
2C$.C29.C2$5.D29.D$5.2D28.2D$4.2D28.2D!

Code: Select all

x = 88, y = 29, rule = LifeHistory
8.2E13.2E41.E$9.E13.E21.2E18.E.E18.2E$6.3E15.3E18.E.E17.E.E17.E.E$6.E
19.E19.E19.E19.E3$2.C19.C19.C19.C19.C$2.3C17.3C17.3C17.3C17.3C$3.C19.
C19.C19.C19.C18$.D19.D19.D19.D19.D$3D17.3D17.3D17.3D17.3D$2.D19.D19.D
19.D19.D!
The third example has two periodic stabilizations (here and here (although the glider-based stabilizaton is probably dependent)) and a StateInvestigator stabilization. On the other hand, the first example was searched with Bellman by Kazyan without any solutions, although Kazyan did mention that he could have done a more thorough search (which I didn't request at the time because I was not yet aware of our lack of ways of making a century with good output clearance). (For a while, I was mistaken and thought that the partial conduit of mine that was searched with Bellman was from my work investigating conduits accepting R−B or R−H, and I didn't check the post and realize that it was my partial C→C/I→R until recently, so if you've seen any posts where I display seemingly unrealistic confidence that the century is good for making conduits with or that it is possible to get a century into positions that seem difficult, that is probably the reason.)



Edit: Stable catalysts are available for two out of three in Symbiosis.

Code: Select all

x = 24, y = 25, rule = Symbiosis
.B$B.A$.2A$.A$.B17.B$18.A.A$19.A9$13.A$12.3A$11.2A3$22.A$23.B$22.BA$11.
2A$11.2A!

Code: Select all

x = 17, y = 12, rule = Symbiosis
10.AB$11.A3$7.A$7.3A$8.A$BA3$16.A$15.B!
For the second, while trying to find a Symbiosis catalyst, I realized that the R-sequence goes back to the same place again, so the catalyst can't recover right away. It is okay if the catalyst interacts with that region again if it waits long enough before doing so, but it definitely makes finding a permanent catalyst (in Symbosis or in ConwayLife) much less plausible.
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Re: History Of ConwayLife

Post by Entity Valkyrie 2 » May 18th, 2021, 5:31 am

The C-to-C conduit also has a StateInvestigator version:

Code: Select all

x = 22, y = 45, rule = StateInvestigator
6.A2$4.3A$4.A2.A$6.2A19$DA$DA$.E$14.E2$17.EDE9$11.3A$10.A2.A$10.2A2$
21.E$21.D$21.B$20.E!
It can be chained:

Code: Select all

x = 26, y = 150, rule = StateInvestigator
15.A2$15.3A$14.A2.A$14.2A19$20.AD$20.AD$20.E$7.E2$2.EDE7$10.A2$8.3A$
8.A2.A$10.2A2$E$D$B$.E14$4.DA$4.DA$5.E$18.E2$21.EDE7$15.A2$15.3A$14.A
2.A$14.2A2$25.E$25.D$25.B$24.E14$20.AD$20.AD$20.E$7.E2$2.EDE7$10.A2$
8.3A$8.A2.A$10.2A2$E$D$B$.E14$4.DA$4.DA$5.E$18.E2$21.EDE9$15.3A$14.A
2.A$14.2A2$25.E$25.D$25.B$24.E!
Bx222 IS MY WORST ENEMY.

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pcallahan
Posts: 845
Joined: April 26th, 2013, 1:04 pm

Re: History Of ConwayLife

Post by pcallahan » June 10th, 2021, 10:42 am

This was my best match for a topic to post a non-technical question about the people involved in Conway's Game of Life.

I have always been curious about Charles Corderman, because unlike other early contributors such as Gosper or Buckingham, I have never heard anything about him besides his list of contributions nearly 50 years ago. This seems unfortunate. The switch engine is a crucial discovery, both as the most frequent natural infinite growth pattern by far, and as the basis of corderships, which are useful workhorses in many engineered patterns.

What's known about him? Is he the same Corderman as this this photo of a Charles Corderman on a ladder working on MIT's Whirlwind computer in the late 1940s?

If so, that would explain a lot about the paucity of recent information. It would be nice to fill in the biographical details on his wiki page.

Update: There is also a Charles Corderman listed in this 1965 conference proceedings. His affiliation is listed as "Scientific Eng. Inst." which even more interestingly is identified as a CIA-funded lab in this 1979 WaPo article. I guess that fits having a long career without leaving too much of a trace.

If anyone actually met Corderman personally, or knows a little more, you may save me from going down a rabbit hole!

Update 2: Lifeline December 1971 covers the switch engine and provides a middle initial L, and a place of residence, Winchester, MA. The middle initial turns up a few other academic references and patents, confirming that I have the right Corderman. He was clearly older than most of the other Life enthusiasts.

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pcallahan
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Joined: April 26th, 2013, 1:04 pm

Re: History Of ConwayLife

Post by pcallahan » June 11th, 2021, 10:59 am

This is probably him, from a genealogy page:
Charles L Corderman
1924 - 1979
BORN September 10, 1924
DEATH February 4, 1979
LAST KNOWN RESIDENCE Winchester, Middlesex County, Massachusetts 01890
SUMMARY Charles L Corderman was born on September 10, 1924. He died on February 4, 1979 at 54 years old. We know that Charles L Corderman had been residing in Winchester, Middlesex County, Massachusetts 01890.
On a personal note, this is eerily close to my father's lifespan 1925-1980. Anyway, it does explain why I never heard much about him directly. From what I can piece together, Corderman was a research assistant at MIT in the late 1940s, worked on the Whirlwind (an early vacuum tube computer), and is on a patent for a CRT storage tube.

He would have been in his late 40s around the time he was contributing to Life, and lived near MIT, though his interaction with Gosper's group is unclear (so again, some living memories could clear up a few things).

It might be nice to put together real biographies one of these days for the early Life innovators. CGOL itself is timeless like all mathematics, but at least some of us enjoy the history.

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