## Search found 5 matches

March 31st, 2013, 10:55 am
Forum: Other Cellular Automata
Topic: cellular automata
Replies: 8
Views: 3749

### Re: cellular automata

I believe that common usage of the word "reversible", in regard to CA, includes, includes what you are calling "Back Trackable" A system is reversible if there is any process that can unabiguously compute a prior state from a current state. We assume that we can compute a future state from a current...
March 30th, 2013, 6:44 pm
Forum: Other Cellular Automata
Topic: cellular automata
Replies: 8
Views: 3749

### Re: cellular automata

The answer to the question you asked is, technically, "Yes". It is easy to difine reversible systems where the state at t+1 is only dependent on the state at time t, and where the state t-1 is, of course, a different function of the state at t. However, those easily defineable reversible systems are...
March 30th, 2013, 1:13 pm
Forum: Other Cellular Automata
Topic: cellular automata
Replies: 8
Views: 3749

### Re: reversible cellular automata

For a CA that is only dependent on the state at time t when the state at time t + 1 is computed you have: b(r, t + 1) = F(N(r, t)) If the CA is time reversible you also have: b(r, t - 1) = F(N(r, t)) So b(r, t + 1) = b(r, t - 1) for every t, which leads to N(r, t) = N(r, t - 2) for every t. And tha...
March 30th, 2013, 9:31 am
Forum: Other Cellular Automata
Topic: Salt, a 3D reversible, universal CA
Replies: 23
Views: 14110

### Re: Salt, a 3D reversible, universal CA

If you read the paper: Circular Motion of Strings... at digitalphilosophy.org, you will understand why microscopic reversibility is a key ingredient (both of physics and models of physics). The SALT model is CPT reversible, as is true of physics.
March 29th, 2013, 9:57 am
Forum: Other Cellular Automata
Topic: Salt, a 3D reversible, universal CA
Replies: 23
Views: 14110

### Salt, a 3D reversible, universal CA

You might find "Circular Motion of Strings in Cellular Automata and Other Suprises" interesting.
It can be found at digitalphilosophy.org
Also, you can see, run and discover new configurations of Salt CA at busyboxes.org