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Hecke category actions via Smith–Treumann theory

Published online by Cambridge University Press:  23 August 2023

J. Ciappara*
Affiliation:
School of Mathematics and Statistics F07, University of Sydney, NSW 2006, Australia joshua.ciappara@sydney.edu.au

Abstract

Let $\textbf {G}$ be a simply connected semisimple algebraic group over a field of characteristic greater than the Coxeter number. We construct a monoidal action of the diagrammatic Hecke category on the principal block $\operatorname {Rep}_0(\textbf {G})$ of $\operatorname {Rep}(\textbf {G})$ by wall-crossing functors. This action was conjectured to exist by Riche and Williamson. Our method uses constructible sheaves and relies on Smith–Treumann theory.

MSC classification

Type
Research Article
Copyright
© 2023 The Author(s). The publishing rights in this article are licensed to Foundation Compositio Mathematica under an exclusive licence

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