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arXiv · 2509.22095

Trivializing Torsors for Difference Algebraic Groups

Annette Bachmayr·Michael Wibmer
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Abstract

We study torsors for groups defined by algebraic difference equations. Our main result provides necessary and sufficient conditions on the base difference field for all such torsors to be trivial. We also present an application to the uniqueness of difference Picard-Vessiot extensions for linear differential equations.

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Annette Bachmayr, Michael Wibmer. 2025-09-26. Trivializing Torsors for Difference Algebraic Groups. https://arxiv.org/abs/2509.22095

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