Today's featured article
|
| A one cell thick pattern is a pattern that is only one cell thick; that is, it is contained entirely within one dimension of the Life plane. Put another way, it is a pattern with bounding box of the form y × 1 for some natural number y. Because of their size restriction, exhaustive computer searches have been carried out to explore one cell thick patterns up to size about 40 × 1. Despite their inherent limitations, one cell thick patterns can exhibit quite complex behavior, even at reasonably small sizes.
In May 1998, Stephen Silver produced a one cell thick pattern that exhibits infinite growth, following a conjecture of Nick Gotts that such patterns exist. This pattern was extremely large (12470 × 1 in the first version, reduced to 5447 × 1 the following day). In October 1998, Paul Callahan performed an exhaustive computer search to find the following pattern that exhibits infinite growth. It is probably the most well-known one cell thick pattern, and Callahan showed that it is the smallest such one cell thick pattern (in terms of its bounding box) to exhibit infinite growth. It contains 28 alive cells and has a 39 × 1 bounding box.
|
In the news
|
- January 1: The much smaller (34,7)c/156 spaceship wins the 2024 Pattern of the Year competition.
- December 27: A five-month-long collaboration concludes when vilc successfully synthesizes the final 23-bit still life for which no glider synthesis was known; a recipe is now available for all 1,646,147 strict still lifes with 23 bits.
- December 23: FWKnightship assembles a self-supporting (28,7)c/448 giraffeship, using a spine made of xWSS convoys that are arranged to release a glider whenever they encounter a block, while moving the block by (7,-28); this mechanism supports limited slow salvo construction equivalent to the arrangements of loaves in a Caterloopillar, but allows for oblique rather than orthogonal travel.
- December 20-21: David Bell builds two "fleet puller" growing spaceships, where the tail end pulls a fleet along with it two diagonal steps at a time, if the fleet is present; otherwise a blinker is alternately created and destroyed.
- December 19: Period1GliderGun constructs a very compact traffic jam signal injector based on the syringe, with the same low repeat time (78 ticks, overclockable to 74 ticks but not 75 since traffic jam wicks are period 2). ElijahKen reduces the repeat time to 597.
- December 17: qqd creates a stable Heisenburp device that can detect passing solifuge spaceships -- or waterbears or other oblique spaceships that use the same technology to turn LWSS streams 90 degrees at a corner.
- December 14-21: Caleb R. Hilton discovers a "wave minstrel", a (2,1)c/6 tagalong for Sir Robin that supports a connection to knightwave -- followed a week later by another completely new minstrel; these are the first new minstrel tagalongs since the baby minstrel appeared in 2023. Both of them are tagalongs to the wandering minstrel, with initial sections that are different from each other and also from the connecting minstrel.
- December 10: Entity Valkyrie builds a stable MWSS-to-HWSS hammer (a device made only from stable circuitry that converts an MWSS directly into an HWSS) in response to a construction challenge.
- December 10: FWKnightship builds an "exponentially spaced binary counter" in response to a construction challenge.
|
|
Did you know...
|
- ... that 84P199 is the current largest prime-period oscillator that is engine-based?
- ... that seven spaceships have been proved to be the smallest possible for their speed and period: glider for period-4 c/4 diagonal, LWSS for period-4 c/2 orthogonal, 64P2H1V0 for period-2 c/2 orthogonal, 30P5H2V0 for period-5 2c/5 orthogonal, 25P3H1V0.1 and 25P3H1V0.2 for period-3 c/3 orthogonal and 37P4H1V0 for period-4 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 Pi-heptomino 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 non-strobing outer-totalistic rules with speed c/2 < v < c have v = 2c/3 or 3c/5, though in strobing rules there are also known spaceships of speed 3c/4 and 5c/8?
- ...that the existence of spaceships in outer-totalistic rules with B23 and S0 and without B01 has been disproven, but of the 8192 such rules without S0, there are spaceships (all of which are p2 photons) known in only 8?
- ...that the cyclic has been rediscovered no less than 13 times?
- ... that Dominoplex and B2ein3cijn4cnrwy5cnq6e/S1c2-ai3acny4anqy5c6ek8 are the first two-state alien isotropic non-totalistic rules with explicitly constructed orthogonoids?
- …that any negative spaceship in a greyship would have to move against the grain, since with the grain ones can only travel at the speed of light, but both greyships and negative spaceships that travel against the grain are more difficult to find, and no c/2 or slower negative spaceship is known?
|
Pattern collection
|
| The LifeWiki contains one of the most comprehensive catalogues of patterns available on the internet. Within it you will find:
|
|
