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On the decidability and complexity of Metric Temporal Logic over finite words

Joel Ouaknine·James Worrell
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Abstract

Metric Temporal Logic (MTL) is a prominent specification formalism for real-time systems. In this paper, we show that the satisfiability problem for MTL over finite timed words is decidable, with non-primitive recursive complexity. We also consider the model-checking problem for MTL: whether all words accepted by a given Alur-Dill timed automaton satisfy a given MTL formula. We show that this problem is decidable over finite words. Over infinite words, we show that model checking the safety fragment of MTL--which includes invariance and time-bounded response properties--is also decidable. These results are quite surprising in that they contradict various claims to the contrary that have appeared in the literature.

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Joel Ouaknine, James Worrell. 2007-02-21. On the decidability and complexity of Metric Temporal Logic over finite words. https://doi.org/10.2168/lmcs-3(1:8)2007

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