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arXiv · 2606.07768

Non-abelian hypercohomology of a group with coefficients in a crossed module, and Galois cohomology

Mikhail Borovoi
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Abstract

We develop a hypercohomology theory of a group with coefficients in a crossed module, and apply it to define abelianization maps for Galois cohomology of reductive algebraic groups.

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Mikhail Borovoi. 2026-06-05. Non-abelian hypercohomology of a group with coefficients in a crossed module, and Galois cohomology. https://arxiv.org/abs/2606.07768

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