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arXiv · 1802.08500

Definable isomorphism problem

Khadijeh Keshvardoost·Bartek Klin·Sławomir Lasota·Joanna Ochremiak·Szymon Toruńczyk
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Abstract

We investigate the isomorphism problem in the setting of definable sets (equivalent to sets with atoms): given two definable relational structures, are they related by a definable isomorphism? Under mild assumptions on the underlying structure of atoms, we prove decidability of the problem. The core result is parameter-elimination: existence of an isomorphism definable with parameters implies existence of an isomorphism definable without parameters.

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Khadijeh Keshvardoost, Bartek Klin, Sławomir Lasota, Joanna Ochremiak, Szymon Toruńczyk. 2018-02-23. Definable isomorphism problem. https://doi.org/10.23638/lmcs-15(4%3A14)2019

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