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arXiv · 2310.04032

The special Brauer group and twisted Picard varieties

Daniel Huybrechts·Dominique Mattei
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Abstract

We generalise the notion of the Tate-Shafarevich group of an elliptic K3 surface with a section to the Tate-Shafarevich group of a K3 surface endowed with a linear system. The construction, which uses Grothendieck's special Brauer group, provides an efficient way to deal with moduli spaces of twisted sheaves supported on curves in a K3 surface.

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Daniel Huybrechts, Dominique Mattei. 2023-10-06. The special Brauer group and twisted Picard varieties. https://arxiv.org/abs/2310.04032

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