This week's featured article
negative is a type of spaceship signal traveling through a periodic agar such as zebra stripes. The leading edge of the signal removes the agar, and the trailing edge rebuilds the agar some time later. The distance between the two edges is sometimes adjustable, as shown in lightspeed bubble. The central part of the "spaceship" may consist of dying sparks or even simple empty space.
In the news
September 19: MathAndCode and Adam P. Goucher construct a 17-glider reverse caber-tosser, proving that all synthesizable patterns can be made with no more than 17 gliders and that all synthesizable still lifes can be constructed with no more than one glider per bit.
September 19: Goldtiger997 synthesizes 55P9H3V0, the first period-9 spaceship to be synthesized.
September 18: Pavel Grankovskiy constructs a complete Speed Demonoid, using double crabstretchers to accelerate a self-constructing spaceship to 3492022/17833792=1746011/8916896 ≈ 0.1958c, very close to c/5. The new spaceship can be adjusted to match any rational speed slower than 2c/9, and could be rebuilt to match any rational speed slower than c/4.
September 15: wwei23 discovers several new 3-engine Corderships, including one that cleans up its trailing blocks with sideways gliders, similar to a 5-, 6-, or 7-in-a-row Cordership. September 9-17: wwei23 assembles a new type of period-192 4-in-a-row Cordership, and later constructs glider-to-Cordership and Cordership-to-glider converters for it.
The LifeWiki contains one of the most comprehensive catalogues of patterns available on the internet. Within it you will find:
Did you know...
Corderships can be constructed using individual switch engines placed arbitrarily far from each other, that will still support each other using intermediary gliders and stable objects? ...
fuses can be made that burn arbitrarily slowly, based on sending spaceships back and forth between two rows of stable objects? ... there exist 'lone dot'
agars consisting of isolated cells in every generation? ... that some types of
spaceship, but not all, support stable Heisenburp technology, where an arrangement of still lifes detects the passage of the spaceship, emits a signal, and returns to its original state? ... that, while it is impossible to build a true
stable Heisenburp device that detects a passing glider without even temporarily affecting it, there are several known stable pseudo-Heisenburp devices? ... that the name of the
Bandersnatch, a color-changing lane-shifter device discovered in 2020, is derived from a Lewis Carroll poem that also supplied names for the Snark, the boojum reflector, and the Bellman search utility? ... that the first
rake that produces spaceships travelling in the same direction but slower was found in 2003, using a c/2 rake to produce 2c/5 spaceships? ... that it is possible for a
single Life object to simulate the evolution of an arbitrary number of other Life objects at the same time (although at increasingly slower speeds)? ... that the
Fast Forward Force Field reaction can transport an LWSS 11 spaces in 6 generations, creating the illusion of super-light-speed travel? ... that there are line puffers with a row of live cells at the back, which create very dirty exhaust whose period apparently (this is not proven) grows exponentially as the length of the row is increased?