Abstract
Topological entropy is an important invariant of topological dynamical systems. It is often regarded as the measure of complexity of the system and can be used to tell non-conjugate systems apart from each other. We will show that the decision problem that asks whether the topological entropy is zero or not is undedicable in the class of reversible one-dimensional cellular automata. We will also show that some related decision problems are also undecidable in the setting of reversible cellular automata and reversible and complete Turing machines.
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The author acknowledges the emmy.network foundation under the aegis of the Fondation de Luxembourg for its financial support.
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Hotanen, T. (2023). Undecidability of the Topological Entropy of Reversible Cellular Automata and Related Problems. In: Genova, D., Kari, J. (eds) Unconventional Computation and Natural Computation. UCNC 2023. Lecture Notes in Computer Science, vol 14003. Springer, Cham. https://doi.org/10.1007/978-3-031-34034-5_8
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