This week's featured article
|The glider (or featherweight spaceship) is the smallest, most common, and first-discovered spaceship. Its name is due in part to the fact that it is glide symmetric. It travels diagonally across the Life grid at a speed of c/4 and is often produced by randomly-generated starting patterns. Gliders are important because they are easily produced (see Gosper glider gun), can be collided with each other to form more complicated objects (see glider synthesis), and can be used to transmit information over long distances.
The glider was found by Richard K. Guy in 1970 while Conway's group was attempting to track the evolution of the R-pentomino. It is often stated that John Conway himself discovered the glider, but he has said that it was Guy.
In the news
- Jan. 26: Dave Greene creates LifeSuper, an extended version of LifeHistory for advanced pattern notation.
- Jan. 26: Entity Valkyrie constructs a period-11040 spider gun, the first gun to fire a c/5 orthogonal spaceship.
- Jan. 13: Matthias Merzenich sets up a new "manually distributed" search (table here), to find out whether a symmetric c/8 spaceship exists at width 19.
- Jan. 9: Nathaniel Johnston completes a long-running enumeration of 34-bit still lifes, finding 35,422,864,104 strict still lifes with 34 bits, and 41,058,173,683 pseudo still lifes with the same bit count, including 26 triple pseudo still lifes.
- Jan. 5: A Rules namespace update on the LifeWiki allows LifeViewer to display in-browser many patterns using rule tables and trees, which previously couldn't be simulated without copying them into Golly.
|The LifeWiki contains one of the most comprehensive catalogues of patterns available on the internet. Within it you will find:
Did you know...
- ... that glider constructions for three previously inconstructible spaceships (the dart, the crab, and the Parallel HBK) were discovered in 2014?
- ... that glider constructions for the B29, X66, half-X66 with HWSS, Pushalong 1, 25P3H1V0.1, 30P5H2V0, 30P4H2V0.4, a pufferfish spaceship, and the weekender were discovered in 2015 — after fifteen years of intermittent efforts in the case of the weekender?
- ... that since 2014, more new spaceship syntheses have been completed than were found in all the years between 1970 and 2013?
- ... that as of 19 January 2020 there are 228 different still lifes known to be constructible by colliding four gliders, but it is likely that this list is not complete?
- ... that in 2014 a new natural infinite growth pattern was discovered, starting from a symmetric random starting configuration?
- ... that the first self-constructing Conway's Life pattern was built in 2010?
- ... that the first glider synthesis for a c/3 spaceship was completed in 2014?
- ... that the first "macro-spaceship" gun (a Gemini spaceship gun) was constructed in 2010, followed by the HBK gun in January 2015 and a Demonoid gun in December 2015?
- ... that the waterbear was the first known high-speed oblique spaceship, many orders of magnitude faster than Gemini spaceships and half-baked 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?