Regular resynchronizability of origin transducers is undecidable

Denis Kuperberg; Jan Martens

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arXiv · 2002.07558

Regular resynchronizability of origin transducers is undecidable

Denis Kuperberg·Jan Martens

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Abstract

We study the relation of containment up to unknown regular resynchronization between two-way non-deterministic transducers. We show that it constitutes a preorder, and that the corresponding equivalence relation is properly intermediate between origin equivalence and classical equivalence. We give a syntactical characterization for containment of two transducers up to resynchronization, and use it to show that this containment relation is undecidable already for one-way non-deterministic transducers, and for simple classes of resynchronizations. This answers the open problem stated in recent works, asking whether this relation is decidable for two-way non-deterministic transducers.

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Denis Kuperberg, Jan Martens. 2020-02-18. Regular resynchronizability of origin transducers is undecidable. https://arxiv.org/abs/2002.07558

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