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arXiv · 1804.00378

Containment Relations among Spherical Subgroups

Johannes Hofscheier
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Abstract

A closed subgroup $H$ of a connected reductive group $G$ is called $\textit{spherical}$ if a Borel subgroup in $G$ has an open orbit on $G/H$. We give a combinatorial characterization for a spherical subgroup to be contained in another one which generalizes previous work by Knop. As an application, we compute the Luna datum of the identity component of a spherical subgroup which yields a characterization of connectedness for spherical subgroups.

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Johannes Hofscheier. 2018-04-02. Containment Relations among Spherical Subgroups. https://arxiv.org/abs/1804.00378

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