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arXiv · 2307.05265

Computing minimal distinguishing Hennessy-Milner formulas is NP-hard, but variants are tractable

Jan Martens·Jan Friso Groote
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Abstract

We study the problem of computing minimal distinguishing formulas for non-bisimilar states in finite LTSs. We show that this is NP-hard if the size of the formula must be minimal. Similarly, the existence of a short distinguishing trace is NP-complete. However, we can provide polynomial algorithms, if minimality is formulated as the minimal number of nested modalities, and it can even be extended by recursively requiring a minimal number of nested negations. A prototype implementation shows that the generated formulas are much smaller than those generated by the method introduced by Cleaveland.

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Jan Martens, Jan Friso Groote. 2023-07-11. Computing minimal distinguishing Hennessy-Milner formulas is NP-hard, but variants are tractable. https://arxiv.org/abs/2307.05265

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