OCA:Pedestrian Life
Pedestrian Life  


View animated image  
Rulestring  23/38 B38/S23 


Rule integer  6408  
Character  Chaotic  
Black/white reversal  B0123478/S1234678 
Pedestrian Life is a Lifelike cellular automaton in which cells survive from one generation to the next if they have 2 or 3 neighbours, and are born if they have 3 or 8 neighbours.
Many patterns from regular Life are compatible with this rule, since the rules differ only in one transition. However, traffic lights are much less common, as most predecessors tend to die, giving the rule its name.^{[1]}
Contents
Notable patterns
The rule is particularly notable for its plurality of distinct natural linear growth mechanisms:
Rotating gun
The first is a statorless, rotating period106 glider gun:^{[2]}
The rotating p106 gun (Catagolue: here) (click above to open LifeViewer) RLE: here Plaintext: here 
(5,2)c/190 spaceships
The second is a family of naturally occurring (5,2)c/190 oblique spaceships, using mechanisms meshed together similarly to switch engines:
The first (5,2)c/190 oblique spaceship found (Catagolue: here) (click above to open LifeViewer) RLE: here Plaintext: here 
There are at least 692 variants of these in the simplest form of two engines,^{[3]} and many more such as one which deletes and recreates a blinker, resulting in a period of 380.^{[4]} Many similar technologies result in puffers, rakes and the like.
Symmetric puffers
The third is a natural 31c/589 diagonallysymmetric ark, which has arisen several times in asymmetric soups. It emits two backward streams of gliders, which can lead to highnovelty interactions. One such example is a 750000generation methuselah in which an ark is born and eventually destroyed by a retrograde glider produced from the chaos hassled by the glider streams.
There is a similar 57c/488 orthogonallysymmetric puffer, but that has only arisen in soups with even orthogonal symmetry.
(101,3)c/1884 oblique puffer
The fourth is a (101,3)c/1884 puffer.^{[5]} Due to its massive ash trails no spaceships have been derived from it.
Universality
The Turingcompleteness of EightLife was mentioned in a poor quality article,^{[6]} but the article failed to list the necessary patterns and reactions inherited from Conway's Game of Life for creating any kind of pattern that proves universality. The same applies to HoneyLife and EightLife; the latter rule has a constructive proof for its Turingcompleteness.
There is a proof sketch of Pedestrian Life's universality. It is on ConwayLife forums,^{[7]} which contains a proofscheme covering all rules in the outertotalistic rulespace between B3/S23 and B3678/S23678.
References
 ↑ Tropylium (April 9, 2013). Re: What do you want out of (conway's) life this year? (discussion thread) at the ConwayLife.com forums
 ↑ DivusIulius (April 10, 2013). [B38/S23] Fourdirectional glider gun (discussion thread) at the ConwayLife.com forums
 ↑ David S. Miller (June 24, 2016). Re: B38/S23 (discussion thread) at the ConwayLife.com forums
 ↑ Apple Bottom (October 27, 2016). Re: Soup search results in rules other than Conway's Life (discussion thread) at the ConwayLife.com forums
 ↑ Adam P. Goucher (November 9, 2016). Re: Soup search results in rules other than Conway's Life (discussion thread) at the ConwayLife.com forums
 ↑ Francisco José Soler Gil, Manuel Alfonesca (July 2013). "Fine tuning explained? Multiverses and cellular automata". Journal for General Philosophy of Science. Retrieved on January 21, 2017.
 ↑ Peter Naszvadi (December 12, 2016). Re: List of the Turingcomplete totalistic lifelike CA (discussion thread) at the ConwayLife.com forums
External links
 Pedestrian Life at Adam P. Goucher's Catagolue
 Pedestrian Life at David Eppstein's Glider Database
 Richard Holmes (20160709). "Big and natural and (5,2)c/190".