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arXiv · 2209.05215

Jordan classes and Lusztig strata in disconnected reductive groups

Martina Costa Cesari
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Abstract

Let $G$ be a non-connected reductive algebraic group over an algebraically closed field $\mathbb{K}$ and let $D$ be a connected component of $G$. We investigate Jordan classes of $D$ and we obtain a description of the regular part of the closure of a Jordan class in terms of induction of $G^{\circ}$-orbits. We use this result to show that Lusztig strata in a non-connected reductive algebraic group are locally closed.

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Martina Costa Cesari. 2022-09-12. Jordan classes and Lusztig strata in disconnected reductive groups. https://arxiv.org/abs/2209.05215

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