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arXiv · 1807.02102

Equivalence checking for weak bi-Kleene algebra

Tobias Kappé·Paul Brunet·Bas Luttik·Alexandra Silva·Fabio Zanasi
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Abstract

Pomset automata are an operational model of weak bi-Kleene algebra, which describes programs that can fork an execution into parallel threads, upon completion of which execution can join to resume as a single thread. We characterize a fragment of pomset automata that admits a decision procedure for language equivalence. Furthermore, we prove that this fragment corresponds precisely to series-rational expressions, i.e., rational expressions with an additional operator for bounded parallelism. As a consequence, we obtain a new proof that equivalence of series-rational expressions is decidable.

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Tobias Kappé, Paul Brunet, Bas Luttik, Alexandra Silva, Fabio Zanasi. 2018-07-05. Equivalence checking for weak bi-Kleene algebra. https://doi.org/10.46298/lmcs-17(3%3A19)2021

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