Signals and omniperiodicity

For discussion of other cellular automata.
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Bullet51
Posts: 712
Joined: July 21st, 2014, 4:35 am

Signals and omniperiodicity

Post by Bullet51 »

To start this thread, here is a signal with repeat time 8 in B3/S023:

Code: Select all

x = 20, y = 39, rule = B3/S023
17b2o$16bobo$16bo$15b2o$13bo$12bob3o$12bo4bo$10bobo3bobo$12b5o2bo$11bo
5b3o$10bob5o$10bo5bob2o$8bobobobo2bobo$10b7o$9bo$8bob7o$8bobo3bo2bo$6b
obo3bo3b2o$8b6o$7bo$6bob6o$6bobo3bo$4bobo3bo3bo$6b6o$5bo$4bob6o$4bobo
3bo$2bobo3bo3bo$4b6o$3bo$2bob6o$2bobo3bo$obo3bo3bo$2b6o$bo6bo$2b6o2$4b
2o$4b2o!
The main purpose of this thread is to find signals and signal turners in order to prove omniperiodicity of some rules.
Omniperiodicity can also be proven by reflectors, but it seems that the repeat time of reflectors is usually too high to prove omniperiodicity.


What to post in this thread:

•Other ways to prove omniperiodicity.
•Signal turners and reflectors.
•Previously unknown signals.
Still drifting.
Sokwe
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Joined: July 9th, 2009, 2:44 pm

Re: Signals and omniperiodicity

Post by Sokwe »

Obviously, this is an old result, but back in 2010 I found signals and signal turners which are sufficient to prove omniperiodicity in rules B3/S234 to B38/S023478.
-Matthias Merzenich
Bullet51
Posts: 712
Joined: July 21st, 2014, 4:35 am

Re: Signals and omniperiodicity

Post by Bullet51 »

Sokwe wrote:Obviously, this is an old result, but back in 2010 I found signals and signal turners which are sufficient to prove omniperiodicity in rules B3/S234 to B38/S023478.
That's pretty good, but what about omniperiodicity in other rules? It seems that calcyman has proven the omniperiodicity of B3/S0123.

EDIT:Actually proven by Dean Hickerson.
Still drifting.
John
Posts: 21
Joined: June 29th, 2015, 4:36 pm

Re: Signals and omniperiodicity

Post by John »

Does anyone know what rules are not omniperiodic?
/S can't have still lifes, but that doesn't say much.
ETA - also obvs, B1 doesn't have oscillators.
-John Cerkan
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