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arXiv · 1704.03160

Lean and Full Congruence Formats for Recursion

Rob van Glabbeek
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Abstract

In this paper I distinguish two (pre)congruence requirements for semantic equivalences and preorders on processes given as closed terms in a system description language with a recursion construct. A lean congruence preserves equivalence when replacing closed subexpressions of a process by equivalent alternatives. A full congruence moreover allows replacement within a recursive specification of subexpressions that may contain recursion variables bound outside of these subexpressions. I establish that bisimilarity is a lean (pre)congruence for recursion for all languages with a structural operational semantics in the ntyft/ntyxt format. Additionally, it is a full congruence for the tyft/tyxt format.

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Rob van Glabbeek. 2017-04-11. Lean and Full Congruence Formats for Recursion. https://arxiv.org/abs/1704.03160

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