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arXiv · 2410.05072

Computing the equivariant Brauer group

Alena Pirutka·Zhijia Zhang
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Abstract

Let X be a smooth projective rational variety carrying a regular action of a finite abelian group G. We give examples of effective computation of the Brauer group of the quotient stack [X/G] in dimensions 2 and 3 using residues in Galois cohomology and the geometry of fixed loci. In particular, we compute Br([X/G]) for all G-minimal del Pezzo surfaces.

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Alena Pirutka, Zhijia Zhang. 2024-10-07. Computing the equivariant Brauer group. https://arxiv.org/abs/2410.05072

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