Wonderful subgroups of reductive groups and spherical systems

Paolo Bravi; Guido Pezzini

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arXiv · 1103.0380

Wonderful subgroups of reductive groups and spherical systems

Paolo Bravi·Guido Pezzini

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Abstract

Let G be a semisimple complex algebraic group, and H a wonderful subgroup of G. We prove several results relating the subgroup H to the properties of a combinatorial invariant S of G/H, called its spherical system. It is also possible to consider a spherical system S as a datum defined by purely combinatorial axioms, and under certain circumstances our results prove the existence of a wonderful subgroup H associated to S. As a byproduct, we reduce for any group G the proof of the classification of wonderful G-varieties, known as the Luna conjecture, to its verification on a small family of cases, called primitive.

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Paolo Bravi, Guido Pezzini. 2011-03-02. Wonderful subgroups of reductive groups and spherical systems. https://arxiv.org/abs/1103.0380

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