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arXiv · 1411.5818

Orbits of strongly solvable spherical subgroups on the flag variety

Jacopo Gandini·Guido Pezzini
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Abstract

Let G be a connected reductive complex algebraic group and B a Borel subgroup of G. We consider a subgroup H of B acting with finitely many orbits on the flag variety G/B, and we classify the H-orbits in G/B in terms of suitable combinatorial invariants. As well, we study the Weyl group action defined by Knop on the set of H-orbits in G/B, and we give a combinatorial model for this action in terms of weight polytopes.

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Jacopo Gandini, Guido Pezzini. 2014-11-21. Orbits of strongly solvable spherical subgroups on the flag variety. https://doi.org/10.1007/s10801-017-0779-x

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