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arXiv · 2509.17929

Arithm\'etique des sous-groupes de Bruhat-Tits sur un anneau de valuation discr\`ete hens\'elien

Anis Zidani
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Abstract

The goal of this paper is to refine some aspects of the cohomological study of Bruhat-Tits subgroups. It aims to complement the work done in the 1987 article. As an application, we obtain a result "\`a la Grothendieck-Serre" for Bruhat-Tits subgroups of a semisimple simply connected group and the exact calculation of the obstruction in the case of quasi-split adjoint groups.

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Anis Zidani. 2025-09-22. Arithm\'etique des sous-groupes de Bruhat-Tits sur un anneau de valuation discr\`ete hens\'elien. https://arxiv.org/abs/2509.17929

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