A classification of unipotent spherical conjugacy classes in bad characteristic

Costantini, Mauro

doi:10.1090/S0002-9947-2011-05390-0

A classification of unipotent spherical conjugacy classes in bad characteristic
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Trans. Amer. Math. Soc. 364 (2012), 1997-2019 Request permission

Abstract:

Let $G$ be a simple algebraic group over an algebraically closed field $k$ of bad characteristic. We classify the spherical unipotent conjugacy classes of $G$. We also show that if the characteristic of $k$ is 2, then the fixed point subgroup of every involutory automorphism (involution) of $G$ is a spherical subgroup of $G$.

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