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arXiv · 2603.05106

Bruhat-Tits group schemes over higher dimensional base-II

Vikraman Balaji·Yashonidhi Pandey
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Abstract

We prove that split reductive BT group schemes over a higher dimensional base are {\em affine}. Our method also gives a new construction of higher BT-group schemes more general than parahoric ones. The new ingredients are an extension of J.-K.Yu's construction in \cite{yu} to higher dimensional bases, N\'eron-Raynaud dilatations of subgroup schemes on divisors, combined with techniques from \cite{bt2} and the structure theory developed in \cite{bp}.

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Vikraman Balaji, Yashonidhi Pandey. 2026-03-05. Bruhat-Tits group schemes over higher dimensional base-II. https://arxiv.org/abs/2603.05106

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