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arXiv · 2103.07557

Languages of Higher-Dimensional Automata

Abstract

We introduce languages of higher-dimensional automata (HDAs) and develop some of their properties. To this end, we define a new category of precubical sets, uniquely naturally isomorphic to the standard one, and introduce a notion of event consistency. HDAs are then finite, labeled, event-consistent precubical sets with distinguished subsets of initial and accepting cells. Their languages are sets of interval orders closed under subsumption; as a major technical step we expose a bijection between interval orders and a subclass of HDAs. We show that any finite subsumption-closed set of interval orders is the language of an HDA, that languages of HDAs are closed under binary unions and parallel composition, and that bisimilarity implies language equivalence.

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Uli Fahrenberg, Christian Johansen, Georg Struth, Krzysztof Ziemiański. 2021-03-12. Languages of Higher-Dimensional Automata. https://arxiv.org/abs/2103.07557

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