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arXiv · 2110.04287

Finiteness of fppf cohomology

Yujie Xu
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Abstract

Let $R$ be a Henselian DVR with finite residue field. Let $G$ be a finite type, flat $R$-group scheme (not necessarily commutative) with smooth generic fiber. We show that $H^1_{\mathrm{fppf}}(\mathrm{Spec} R,G)$ is finite. We then give an application of the global analogue of this finiteness result to PEL type integral models of Shimura varieties.

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Yujie Xu. 2021-10-08. Finiteness of fppf cohomology. https://arxiv.org/abs/2110.04287

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