A universal cellular automaton in the hyperbolic plane
The paper gives the construction of a universal CA with 22 states in the regular rectangular pentagonal grid of the hyperbolic plane. The CA implements a-railway circuit which simulates a register machine and which improves a bit already known railway simulations of a Turing machine. (C) 2002 Elsevier Science B.V. All rights reserved.
universality hyperbolic plane circuits registers switches cellular automata