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arXiv · 2205.11114

Algebraicity and smoothness of fixed point stacks

Matthieu Romagny
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Abstract

We study algebraicity and smoothness of fixed point stacks for flat group schemes which have a finite composition series whose factors are either reductive or proper, flat, finitely presented, acting on algebraic stacks with affine, finitely presented diagonal. For this, we extend some theorems of [SGA3.2] on functors of homomorphisms Hom(G, H) and functors of reductive subgroups Sub(H) for an affine, possibly non-flat group scheme H.

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Matthieu Romagny. 2022-05-23. Algebraicity and smoothness of fixed point stacks. https://arxiv.org/abs/2205.11114

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