This week's featured article

Glider synthesis (or glider construction) is the construction of an object by means of glider collisions. It is generally assumed that the gliders should be arranged so that they could come from infinity  that is, gliders should not have had to pass through one another to achieve the initial arrangement.
Four main characterizing features of a synthesis are the geometry, reaction speed, reaction multiplicity, and glider cost. Of particular interest is slow salvo synthesis: unidirectional synthesis where every stage has a glider cost of one, and thus the number of stages (i.e., the multiplicity) is equal to the total cost. Perhaps surprisingly, anything that is glider synthesizable is also slow salvo synthesizable.
In the 1990s, glider syntheses for all still lifes and known oscillators with at most 14 cells were found by David Buckingham. Almost all of these were successfully reduced to a synthesis cost of less than 1 glider per live cell, or "1 glider per bit". A collaborative effort ending in May 2014 completed glider syntheses of all still lifes with 17 or fewer cells. A second, longer effort completed all the 18bit still lifes in November 2014. Later optimization projects reduced the maximum cost of construction for 15bit and 16bit still lifes to less than one glider per bit.

In the news

 August 1: Voting begins for the 2023 Pattern of the Year contest, with voting set to end at the end of August.
 July 31: Keith Amling proves that the 140cell statorless p3 is the unique smallest possible statorless period3 oscillator in terms of its minimum population.
 July 27: A longterm effort by May13 starting back in January brings the number of unsynthesized 22bit still lifes down to below 400, with several people contributing more syntheses since then.
 July 26: Period1GliderGun discovers 86P118, the smallest known period118 oscillator, based on a partial by iNoMed.
 July 16: Entity Valkyrie reduces the best known highway robber recovery time from 742 ticks to 651 ticks.
 July 4: Entity Valkyrie improves the repeat time of the 2c/3 receiver from 742 ticks to 708, using a bronco, a Jubjub reflector, and an alternate shipandbeehive bait proposed by Simon Ekström.
 July 3: A recent optimization effort orchestrated by Vort starting in June, with many contributions by confocaloid, LouisFrançois Handfield, and others, has greatly reduced the maximum and average sizes of guns with fourdigit prime periods.


Did you know...

 ...that the smallest c/4 diagonal spaceship that does not contain any gliders (including temporary gliders) is more than 13 times larger than the glider?
 ...that no spaceships have been found that work in both Life (B3/S23) and Grounded Life (B35/S23), despite the fact that these rules are only one outertotalistic transition apart?
 ... that there are at least five distinct patterns which can be referred to using the word 'wing', namely Wing, Wing (spaceship), Wings, Flying wing and any thin component that protrudes from a spaceship in a direction not parallel to the direction of travel?
 ... that there are four unrelated SKOPs for p7 with a population of 28: Burloaferimeter, 28P7.1, 28P7.2 and 28P7.3?
 ... that 84P199 is the current largest primeperiod oscillator that is enginebased?
 ... that seven spaceships have been proved to be the smallest possible for their speed and period: glider for period4 c/4 diagonal, LWSS for period4 c/2 orthogonal, 64P2H1V0 for period2 c/2 orthogonal, 30P5H2V0 for period5 2c/5 orthogonal, 25P3H1V0.1 and 25P3H1V0.2 for period3 c/3 orthogonal and 37P4H1V0 for period4 c/4 orthogonal?
 ... that the LWSS, MWSS and HWSS are the only known polyomino spaceships for more than 50 years?
 ..that Burloaferimeter is the only known oscillator with a heat lower than 2?
 ...that despite the Piheptomino being known for over 50 years and its notable forward motion, it has not been stabilised to a 3c/10 spaceship yet?
 ...that the only known orthogonal spaceships in nonstrobing outertotalistic rules with speed c/2 < v < c have v = 2c/3, though in strobing rules there are also known spaceships of speed 3c/4 and 5c/8?

Pattern collection

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

