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arXiv · 2409.06006

Inequalities characterizing distinguished unipotent orbits

Abstract

In this paper we prove a new characterization of the distinguished unipotent orbits of a connected reductive group over an algebraically closed field of characteristic 0. For classical groups we prove the characterization by a combinatorial computation, and for exceptional groups we check it with a computer. This characterization is needed in the theory of cuspidal sheaves on the stack of L-parameters in forthcoming work of the first two named authors.

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Alexander Bertoloni Meli, Teruhisa Koshikawa, Jonathan Leake. 2024-09-09. Inequalities characterizing distinguished unipotent orbits. https://arxiv.org/abs/2409.06006

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