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arXiv · 2212.03772

Automorphisms and twisted forms of rings of invariants

János Kollár
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Abstract

Let $G\subset GL_n(k)$ be a finite subgroup and $k[x_1,\dots, x_n]^G\subset k[x_1,\dots, x_n]$ its ring of invariants. We show that, in many cases, the automorphism group of $k[x_1,\dots, x_n]^G$ is $k^\times$. Version 2: Incorporates parts of arXiv:2210.16265.

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János Kollár. 2022-12-07. Automorphisms and twisted forms of rings of invariants. https://arxiv.org/abs/2212.03772

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