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arXiv · 2310.04029

Splitting unramified Brauer classes by abelian torsors and the period-index problem

Daniel Huybrechts·Dominique Mattei
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Abstract

We use twisted relative Picard varieties to split Brauer classes on projective varieties over algebraically closed fields by torsors for a fixed abelian scheme independent of the Brauer class. The construction is also used to prove that the index of an unramified Brauer class divides a fixed power of its period.

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Daniel Huybrechts, Dominique Mattei. 2023-10-06. Splitting unramified Brauer classes by abelian torsors and the period-index problem. https://arxiv.org/abs/2310.04029

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