Today's featured article
|
A methuselah is, roughly speaking, a pattern that takes a large number of generations in order to stabilize (known as its lifespan) and becomes much larger than its initial configuration at some point during its evolution. In particular, patterns that grow forever are not methuselahs. Their exact definition is not completely agreed upon, and most definitions place restrictions on the number of cells in the initial pattern.
Martin Gardner defined methuselahs as patterns of fewer than ten cells that take longer than 50 generations to stabilize, though some sources allow for more cells or require a longer lifespan.
|
In the news
|
- December 11: Matthias Merzenich completes a very high-clearance period-7 middleweight sparker based on a partial result by hotcrystal0.
- December 5: Matthias Merzenich completes the first true period-35 glider gun based on a partial result by iNoMed and hotcrystal0.
- November 18: AlbertArmStain discovers a small, direct H-to-MWSS conduit with a repeat time of 141 ticks. Period1GliderGun and Lucy D'Agostino subsequently find variants that reduce the repeat time to 120 ticks.
- November 3: Lucy D'Agostino discovers a new set of connectable Spartan converters with E-heptomino inputs, further expanding the set of known E-heptomino conduits.
- November 2: iNoMed finds a way to use stable catalysts to make a p2 traffic jam wire turn a 90-degree corner with no help from sparkers.
- October 28-30: Entity Valkyrie builds the first known true period-47 glider gun based on a partial result by iNoMed, after which the bounding box is reduced by more than a factor of four by several contributors over the next two days, from 311 × 289 down to Luka Okanishi's greatly simplified design at 147 × 144.
- October 20: FWKnightship completes a redesigned (34,7)c/156 spaceship with a bounding box of (52514, 158980) and minimum population of 655,594; this is less than 1/38th of the population and less than 1/6000th of the area of the previous version of this spaceship constructed by Luka Okanishi last year.
- October 10: AlbertArmstain rebuilds an initial stage from Mitchell Riley's H-to-Gs into a Herschel-to-B-heptomino converter; Lucy D'Agostino notices that this is actually a known E-heptomino converter appended to a previously unknown Herschel-to-E converter, HRx93E -- which enables completely new Spartan Herschel conduits Rx155 and R194, among other things.
- October 10: Mitchell Riley's "LightCone" search program finds several new Spartan Herschel-to-glider converters.
- October 9: Tanner Jacobi reduces the cost of the synthesis for B29 from 25 to 16 gliders, using QuFince to avoid scaffolding.
- October 9: Chris857 finds a synthesis for popover.
|
|
Did you know...
|
- ... that most greyships travel parallel to the stripes in their included agars, but a few travel perpendicular to the stripes, or "against the grain"?
- ... that a pattern has been constructed that calculates and prints out the digits of pi in decimal, and a similar one prints out the decimal digits of the Golden Ratio?
- ... that several different patterns have been constructed to calculate and display the sequence of prime numbers, and some have been adapted to display only twin primes or Fermat primes?
- ... that two completely different types of oblique spaceships, the waterbear and the half-baked knightship, were constructed in 2014?
- ... that no Caterpillar-type spaceships were completed for almost ten years after the original Caterpillar was constructed in 2004, but that two different designs, the waterbear and the centipede, were finished in 2014?
- ... that the first spiral-growth pattern in Conway's Life was constructed in 2014?
- ... that among known glider recipes for irreducible objects, the Gemini spaceship has the largest known minimal recipe not counting encoded RCT recipes, currently 173,449 gliders — the runner-up being the self-synthesizing oblique loopship which is its own 144,221-glider synthesis?
- ... that it was shown in 2014 that any salvo of gliders, no matter how tightly packed, can be constructed by crashing together gliders whose initial positions are farther apart than any chosen finite distance?
- ... that no spaceships with velocities other than c/4 diagonal (glider), c/2 orthogonal (*WSS variants), and c/12 diagonal (Corderships) had known glider syntheses until 2003, when a 2c/5 spaceship gun was constructed?
- ... that after ten years with no new small spaceship syntheses, a glider construction was found for the c/7 loafer in 2013 less than three hours after its discovery?
|
Pattern collection
|
The LifeWiki contains one of the most comprehensive catalogues of patterns available on the internet. Within it you will find:
|
|