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arXiv · 1801.00089

Essential dimension of finite groups in prime characteristic

Zinovy Reichstein·Angelo Vistoli
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Abstract

Given a finite smooth group scheme $G$ over a field of characteristic $p > 0$, we show that the essential dimension of $G$ at $p$ is $0$ when $p$ does not divide the order of $G$, and $1$ when it does.

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Zinovy Reichstein, Angelo Vistoli. 2017-12-30. Essential dimension of finite groups in prime characteristic. https://arxiv.org/abs/1801.00089

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