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arXiv · 2212.10182

Fixed points under pinning-preserving automorphisms of reductive group schemes

Pramod N. Achar·João Lourenço·Timo Richarz·Simon Riche
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Abstract

In this paper we determine the scheme-theoretic fixed points of pinned reductive group schemes acted upon by a group of pinning-preserving automorphisms. The results are used in a companion paper to establish a ramified geometric Satake equivalence with integral or modular coefficients.

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Pramod N. Achar, João Lourenço, Timo Richarz, Simon Riche. 2022-12-20. Fixed points under pinning-preserving automorphisms of reductive group schemes. https://arxiv.org/abs/2212.10182

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