This week's featured article

The grandfather problem is the following question, posed by John Conway in 1972 in Lifeline Volume 6:
 Is there a configuration which has a father but no grandfather?
Conway offered a $50 cash prize to "the first person to settle the grandfather problem either way". But the problem remained open until May 2016, when mtve presented such a pattern  and, soon after that, a pattern with a grandfather but no greatgrandfather, and another pattern with a greatgrandfather but no greatgreatgrandfather.

In the news

 Mar. 7: A spider synthesis using 574 gliders and 9 LWSSes is found by Martin Grant. [1]
 Mar. 3: A period120 oscillator, the highest period thus far, occurs from a natural soup on Catagolue.
 Mar. 2: Several symmetricsoup diehards with lifespans over 1500 ticks have been found by 'carybe', using apgsearch..
 Feb. 12: A lightweight Schick engine appears from a natural (C1) soup on Catagolue.
 Feb. 9: A 47,575tick 16x16 methuselah found by Adam Goucher via apgsearch yields a 16cell, 47,487tick methuselah. This discovery skips over several empty 1000tick bins in Catagolue above the previous record 16x16 methuselah, Homer.
 Feb. 4: A glider detection and removal upgrade in apgsearch version 4.91 gives a search speed boost of well over 50% compared to version 4.88.
 Feb. 4: Tanner Jacobi and Martin Grant find a recipe, subsequently reduced to 88 gliders, for the firstever synthesizable c/4 spaceship, 46P4H1V0.

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 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 or 53?
 ...that without the use of Herschel loops or adjustable glider loops, there are no known oscillators with periods 59 or 61?
 ... that small stable elementary period multipliers (also known as pulse dividers) have been found for multipliers of 2x, 3x, and 4x, but not for 5x or higher?
 ... that with reverse cabertosser universal constructor technology, it is possible to build any possible gliderconstructible pattern, no matter what size, using only 35 gliders?
 ... that there are at least four known ways to send information diagonally at a speed greater than the maximum spaceship speed through vacuum? (Complete mechanisms include speeds approaching c/2 via two perpendicular telegraphs, and 2c/3 via a 2c/3 wire.)
 ... that an oscillator with strict volatility 1 can be constructed for any period 3506909 or higher?
 ... that the original Gemini's "belowtheelbow" construction efficiency, roughly three gliders per still life, is about four times better than that of any subsequent selfconstructing spaceship?

