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arXiv · 1006.3451

An upper bound on the number of states for a strongly universal hyperbolic cellular automaton on the pentagrid

Maurice Margenstern
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Abstract

In this paper, following the way opened by a previous paper deposited on arXiv, we give an upper bound to the number of states for a hyperbolic cellular automaton in the pentagrid. Indeed, we prove that there is a hyperbolic cellular automaton which is rotation invariant and whose halting problem is undecidable and which has 9~states.

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Maurice Margenstern. 2010-06-17. An upper bound on the number of states for a strongly universal hyperbolic cellular automaton on the pentagrid. https://arxiv.org/abs/1006.3451

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