Partial orders on conjugacy classes in the Weyl group and on unipotent conjugacy classes

Jeffrey Adams; Xuhua He; Sian Nie

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arXiv · 2004.01337

Partial orders on conjugacy classes in the Weyl group and on unipotent conjugacy classes

Jeffrey Adams·Xuhua He·Sian Nie

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Abstract

Let $G$ be a reductive group over an algebraically closed field and let $W$ be its Weyl group. In a series of papers, Lusztig introduced a map from the set $[W]$ of conjugacy classes of $W$ to the set $[G_u]$ of unipotent classes of $G$. This map, when restricted to the set of elliptic conjugacy classes $[W_e]$ of $W$, is injective. In this paper, we show that Lusztig's map $[W_e] \to [G_u]$ is order-reversing, with respect to the natural partial order on $[W_e]$ arising from combinatorics and the natural partial order on $[G_u]$ arising from geometry.

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BibTeX RIS

Jeffrey Adams, Xuhua He, Sian Nie. 2020-04-03. Partial orders on conjugacy classes in the Weyl group and on unipotent conjugacy classes. https://arxiv.org/abs/2004.01337

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