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arXiv · 2110.09911

Predicate and relation liftings for coalgebras with side effects: an application in coalgebraic modal logic

H. Beohar·B. König·S. Küpper·C. Mika-Michalski
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Abstract

We study coalgebraic modal logic to characterise behavioural equivalence in the presence of side effects, i.e., when coalgebras live in a (co)Kleisli or an Eilenberg-Moore category. Our aim is to develop a general framework based on indexed categories/fibrations that is common to the aforementioned categories. In particular, we show how the coalgebraic notion of behavioural equivalence arises from a relation lifting (a special kind of indexed morphism) and we give a general recipe to construct such liftings in the above three cases. Lastly, we apply this framework to derive logical characterisations for (weighted) language equivalence and conditional bisimilarity.

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H. Beohar, B. König, S. Küpper, C. Mika-Michalski. 2021-10-19. Predicate and relation liftings for coalgebras with side effects: an application in coalgebraic modal logic. https://arxiv.org/abs/2110.09911

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