OCA:EightLife
| EightLife | |
| View static image | |
| View animated image | |
| Rulestring | 238/3 B3/S238 |
|---|---|
| Rule integer | 137224 |
| Character | Chaotic |
| Black/white reversal | B123478/S01234678 |
EightLife (or Pulsar Life[1]) is a Life-like cellular automaton in which a cell survives from one generation to the next if it has 2, 3 or 8 neighbours, and is born if it has 3 neighbours.
Patterns
Many patterns from regular Life are compatible with this rule, but there are exceptions, like the heavyweight spaceship which does not survive. Pulsars are common, as the name "Pulsar Life" suggests, evolving from the pi heptomino. Honeycombs are also common, because a common spark in Life (specifically the line-of-six spark, the one hassled in worker bee) evolves into this pattern instead. The pentadecathlon evolves differently in a few phases but is still period 15 and retains its domino spark and other capabilities.
Oscillators
Many alien oscillators which don't work, or evolve differently, in Life exist in this rule, several of which are shown below:
| A period-20 oscillator (40P20) (click above to open LifeViewer) Catagolue: here |
| A period-22 oscillator (14P22) [2] (click above to open LifeViewer) Catagolue: here |
| Eight R-pentominoes stabilize themselves in D8 symmetry, becoming a period-23 oscillator (40P23).[3] The closest equivalents in regular Life are Gabriel's p138 and Karel's p177. There is a p23 Herschel/R-pentomino hassler using this oscillator[4] (click above to open LifeViewer) Catagolue: here |
| A period-38 flipper oscillator (24P38)[5] (click above to open LifeViewer) Catagolue: here |
| A period-8 oscillator (120P8)[6] (click above to open LifeViewer) Catagolue: here |
| Two alien period-2 oscillators,[7] 10P2 (Catagolue: here) and 13P2 (Catagolue: here) (click above to open LifeViewer) |
Soup search
- See also: Catagolue, Tutorials/Contributing to Catagolue
The b3s238/C1 census on Catagolue accumulated over 8 billion objects by April 2015,[c 1] over 137 billion objects by October 2017,[c 2] over 193 billion objects by October 2020,[c 3] over 591 billion objects by July 2021,[c 4] over 604 billion objects by November 2021,[c 5] over 690 billion objects by December 2022,[c 6] over 900 billion objects by February 2023.[c 7]
On March 4, 2023, the b3s238/C1 census reached a total of one trillion objects,[c 8] making EightLife one of several Life-like rules with hauls subject to statistical verification and peer review before being committed.
Universality
The universality of EightLife was mentioned in an article published in Journal for General Philosophy of Science.[8] The first true proof was published on the ConwayLife forums[9] in the form of a Rule 110 unit cell, which was inherited from Conway's Game of Life and constructed by Jason Summers.[10]
On November 21, 2017, Peter Naszvadi constructed another Rule 110 unit cell in EightLife.[11] The pattern is based on eater 1, middleweight spaceship, twin bees shuttle and p46 gliderless MWSS gun, therefore it also applies to Pedestrian Life and HoneyLife.
References
- ↑ Tropylium (April 9, 2013). Re: What do you want out of (conway's) life this year? (discussion thread) at the ConwayLife.com forums
- ↑ velcrorex (September 24, 2014). Re: Thread for Your Accidental Discoveries that Aren't in CGOL (discussion thread) at the ConwayLife.com forums
- ↑ velcrorex (March 9, 2015). Re: Soup search results in rules other than Conway's Life (discussion thread) at the ConwayLife.com forums
- ↑ wwei47 (March 25, 2021). Re: Miscellaneous Discoveries in Other Cellular Automata (discussion thread) at the ConwayLife.com forums
- ↑ Carson Cheng (March 29, 2023). Re: B3/S238 (discussion thread) at the ConwayLife.com forums
- ↑ wwei47 (May 20, 2021). Re: Miscellaneous Discoveries in Other Cellular Automata (discussion thread) at the ConwayLife.com forums
- ↑ bubblegum (October 13, 2020). Re: B3/S238 (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). List of the Turing-complete totalistic life-like CA (discussion thread) at the ConwayLife.com forums
- ↑ "Rule 110" Unit Cell at Game of Life News. Posted by Heinrich Koenig on December 21, 2005.
- ↑ Peter Naszvadi (November 21, 2017). FWSS-less MWSS-track-only Rule-110 Unit Cell (discussion thread) at the ConwayLife.com forums
- Catagolue
- ↑ /census (archived copy as of 2015-04-22)
- ↑ /census/b3s238/C1 (archived copy as of 2017-10-29)
- ↑ /census (archived copy as of 2020-10-27)
- ↑ /census/b3s238 (archived copy as of 2021-07-18)
- ↑ /census/b3s238/C1 (archived copy as of 2021-11-22)
- ↑ /census (archived copy as of 2022-12-05)
- ↑ /census/b3s238/C1 (archived copy as of 2023-02-21)
- ↑ /census/b3s238/C1, /haul/b3s238/C1 (archived copies as of 2023-03-04)
External links
- EightLife at Adam P. Goucher's Catagolue
- EightLife at David Eppstein's Glider Database
- B3/S238 (discussion thread) at the ConwayLife.com forums