This week's featured article

A Garden of Eden is a pattern that has no parents and thus can only occur in generation 0. The term was first used in connection with cellular automata by John W. Tukey, many years before Conway's Game of Life was conceived. It was known from the start that Gardens of Eden exist in Life because of a theorem by Edward Moore that guarantees their existence in a wide class of cellular automata. The first Garden of Eden was found by Roger Banks and the MIT group in 1971. It had a bounding box of size 33 × 9 and 226 cells. Jean HardouinDuparc found the second and third Gardens of Eden by computer search in 1973, which had bounding boxes of size 122 × 6 and 117 × 6. His goal was to find Gardens of Eden with minimal height. In April 2016, Steven Eker found a Garden of Eden fitting inside a 5 x 83 bounding box. It is known that no Gardens of Eden exist with height less than 4, but the question is still open for the h=4 case.

In the news


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 it can be proved reflectorless rotating oscillators exist in Life, although none have yet been found or constructed?
 ...that there are currently known elementary spaceships with speeds c/7 and c/10 orthogonal, but none with c/8 or c/9?
 ...that there are currently known elementary spaceships with speeds c/7 and c/12 diagonal, but none with c/8, c/9, c/10 or c/11?
 ...that while the speed limit for orthogonal spaceships in rules using the Moore neighbourhood is c orthogonal, spaceships in Larger than Life rules are capable of breaking this barrier?
 ...that without the use of adjustable glider loops, there are no known oscillators with periods 43, 49 or 53?
 ...that without the use of Herschel loops or adjustable glider loops, there are no known oscillators with periods 57, 59 or 61?
 ... that the largest interesting pattern constructed, the caterpillar, contains over 11 million cells?
 ... that the Gosper glider gun was the first pattern to be discovered that exhibits infinite growth?
 ... that the blocklaying switch engine and the gliderproducing switch engine (and various combinations of two switch engines) are the only infinitelygrowing patterns that are known to have ever occurred naturally from an asymmetric random starting configuration?
 ... that oscillators are known that oscillate at all periods other than 19, 23, 34, 38 and 41?

