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arXiv · 2505.10386

Classifying torsors of tori with Brauer groups

Alexander Duncan·Pankaj Singh
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Abstract

Using Mackey functors, we provide a general framework for classifying torsors of algebraic tori in terms of Brauer groups of finite field extensions of the base field. This generalizes Blunk's description of the tori associated to del Pezzo surfaces of degree 6 to all retract rational tori, essentially the largest class for which this is possible.

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Alexander Duncan, Pankaj Singh. 2025-05-15. Classifying torsors of tori with Brauer groups. https://arxiv.org/abs/2505.10386

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