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arXiv · 1202.1709

A family of weakly universal cellular automata in the hyperbolic plane with two states

Maurice Margenstern
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Abstract

In this paper, we construct a family of weakly universal rotation invariant cellular automaton for all grids $\{p,3\}$ of the hyperbolic plane for $p\geq 13$. The scheme is general for $p\geq 17$ and for $13\leq p<17$, we give such a cellular automaton for $p=13$, which is enough. Also, an important property of this family is that the set of cells of the cellular automaton which are subject to changes is actually a planar set. The problem for $p<13$ for a truly planar construction is still open. The best result, for $p=7$, is four states and was obtained by the same author.

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Maurice Margenstern. 2012-02-08. A family of weakly universal cellular automata in the hyperbolic plane with two states. https://arxiv.org/abs/1202.1709

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