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arXiv · 1408.3347

Spherical subgroups of Kac-Moody groups and transitive actions on spherical varieties

Abstract

We define and study a class of spherical subgroups of a Kac-Moody group. In analogy with the standard theory of spherical varieties, we introduce a combinatorial object associated with such a subgroup, its homogeneous spherical datum, and we prove that it satisfies the same axioms as in the finite-dimensional case. Our main tool is a study of varieties that are spherical under the action of a connected reductive group L, and come equipped with a transitive action of a group containing L as a Levi subgroup.

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Guido Pezzini. 2014-08-14. Spherical subgroups of Kac-Moody groups and transitive actions on spherical varieties. https://arxiv.org/abs/1408.3347

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