Unipotent character sheaves and strata of a reductive group

Lusztig, G.

doi:10.1090/ert/663

Unipotent character sheaves and strata of a reductive group
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by G. Lusztig;

Represent. Theory 27 (2023), 1126-1141

DOI: https://doi.org/10.1090/ert/663

Published electronically: November 29, 2023

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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.

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