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arXiv · 2210.15743

Picard sheaves, local Brauer groups, and topological modular forms

Benjamin Antieau·Lennart Meier·Vesna Stojanoska
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Abstract

We prove that the Brauer group of TMF is isomorphic to the Brauer group of the derived moduli stack of elliptic curves. Then, we compute the local Brauer group, i.e., the subgroup of the Brauer group of elements trivialized by some étale cover of the moduli stack, up to a finite 2-torsion group.

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Benjamin Antieau, Lennart Meier, Vesna Stojanoska. 2022-10-27. Picard sheaves, local Brauer groups, and topological modular forms. https://arxiv.org/abs/2210.15743

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