This week's featured article

A finite pattern is said to exhibit infinite growth if it is such that its population is unbounded. That is, for any number N there exists a generation n such that the population in generation n is greater than N. The first known pattern to exhibit infinite growth was the Gosper glider gun. In 1971, Charles Corderman found that a switch engine could be stabilized by a preblock in a number of different ways to produce either a blocklaying switch engine or a gliderproducing switch engine, giving several 11cell patterns with infinite growth. This record for smallest infinitelygrowing pattern stood for more than quarter of a century until Paul Callahan found, in November 1997, two 10cell patterns with infinite growth. Nick Gotts and Paul Callahan have since shown that there is no infinite growth pattern with fewer than 10 cells, so the question of the smallest infinite growth pattern in terms of number of cells has been answered completely.

Pattern collection

The LifeWiki contains one of the most comprehensive catalogues of patterns available on the internet. Within it you will find:


Did you know...

 ... that the waterbear is the single known highspeed oblique spaceship, many orders of magnitude faster than Gemini spaceships and halfbaked knightships?
 ... that there are no known direct reflectors for lightspeed wire signals, or for signals in 2c/3 wires, but that very large reflectors for these signals can be constructed using stable or periodic circuitry?
 ... that 24 tencell patterns exhibit infinite growth, with 17 unique pattern types, but that it has been proven that no ninecell pattern exhibits infinite growth?
 ... that all still lifes up to 18 bits have a known glider synthesis, but it is still not known whether all still lifes are synthesizable?
 ... that the French kiss remained without a glider synthesis until 2013?
 ... that Adam P. Goucher's distributed Catagolue soupsearch project, started in February 2015, has already tested more random soups than any previous such project, and has contributed to the reduction of many glider construction recipes?
 ... that any gliderconstructible Life pattern can be constructed with a fixed maximum number of gliders N, probably less than 1000? It is only necessary to construct a slidingblock decoder, which selfdestructs after converting the position of a fardistant block into a slowsalvo recipe that constructs the required pattern.
 ... that Copperhead is not only the first c/10 orthogonal spaceship ever found, but also remarkably compact for a pattern not discovered until 2016?
 ... that loafer is the fifth smallest nonflotilla spaceship, but was discovered 43 years after the four spaceships smaller than it?
 ... that despite being the fourth smallest nonflotilla orthogonal spaceship, loafer has never appeared from a single randomly generated soup?

