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arXiv · 2209.02069

Criterion for surjectivity of localization in Galois cohomology of a reductive group over a number field

Mikhail Borovoi·Zev Rosengarten
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Abstract

Let $G$ be a connected reductive group over a number field $F$, and let $S$ be a set (finite or infinite) of places of $F$. We give a necessary and sufficient condition for the surjectivity of the localization map from $H^1(F,G)$ to the "direct sum" of the sets $H^1(F_v,G)$ where $v$ runs over $S$. In the appendices, we give a new construction of the abelian Galois cohomology of a reductive group over a field of arbitrary characteristic.

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BibTeXRIS

Mikhail Borovoi, Zev Rosengarten. 2022-09-05. Criterion for surjectivity of localization in Galois cohomology of a reductive group over a number field. https://arxiv.org/abs/2209.02069

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