Cohomological invariants and Brauer groups of algebraic stacks in positive characteristic

Andrea Di Lorenzo; Roberto Pirisi

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arXiv · 2207.08792

Cohomological invariants and Brauer groups of algebraic stacks in positive characteristic

Andrea Di Lorenzo·Roberto Pirisi

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Abstract

We introduce a theory of cohomological invariants with mod $p^r$ coefficients for algebraic stacks in characteristic $p$. Using these new tools we complete the computation of the Brauer group and cohomological invariants of the stack of elliptic curves over any field.

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Andrea Di Lorenzo, Roberto Pirisi. 2024-03-24. Cohomological invariants and Brauer groups of algebraic stacks in positive characteristic. https://arxiv.org/abs/2207.08792

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