Unipotent character sheaves and strata of a reductive group

2022/10/26 by G. Lusztig, Lusztig, G.
Mathematics · #Advanced Algebra and Geometry #Algebraic Geometry and Number Theory #Algebraic structures and combinatorial models #FOS: Mathematics #Representation Theory (math.RT)

paper · pdf · doi:10.48550/arxiv.2210.14422

openalex publication_date 2022/10/26 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28

Abstract

Let H be a connected reductive group over an algebraically closed field. We define a surjective map from the set CS(H) of unipotent character sheaves on H (up to isomorphism) to the set of strata of H. To do this we use the generalized Springer correspondence. We also give a new parametrization of CS(H) in terms of data coming from bad characteristic. Some minor errors corrected.

Related

• Unipotent character sheaves and strata of a reductive group, II
• Character sheaves on disconnected groups, X
• Non-unipotent character sheaves as a categorical centre
• Restriction of a character sheaf to conjugacy classes
• Character sheaves on disconnected groups, II