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arXiv · 2002.11459

Explaining Non-Bisimilarity in a Coalgebraic Approach: Games and Distinguishing Formulas

Barbara König·Christina Mika-Michalski·Lutz Schröder
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Abstract

Behavioural equivalences can be characterized via bisimulation, modal logics, and spoiler-duplicator games. In this paper we work in the general setting of coalgebra and focus on generic algorithms for computing the winning strategies of both players in a bisimulation game. The winning strategy of the spoiler (if it exists) is then transformed into a modal formula that distinguishes the given non-bisimilar states. The modalities required for the formula are also synthesized on-the-fly, and we present a recipe for re-coding the formula with different modalities, given by a separating set of predicate liftings. Both the game and the generation of the distinguishing formulas have been implemented in a tool called T-BEG.

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Barbara König, Christina Mika-Michalski, Lutz Schröder. 2020-10-14. Explaining Non-Bisimilarity in a Coalgebraic Approach: Games and Distinguishing Formulas. https://doi.org/10.1007/978-3-030-57201-3_8

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