Perverse $\mathbb{F}_p$-sheaves on the affine Grassmannian
Autor: | Cass, Robert |
---|---|
Rok vydání: | 2019 |
Předmět: | |
Zdroj: | J. Reine Angew. Math. 785 (2022), 219-272 |
Druh dokumentu: | Working Paper |
Popis: | For a reductive group over an algebraically closed field of characteristic $p > 0$ we construct the abelian category of perverse $\mathbb{F}_p$-sheaves on the affine Grassmannian that are equivariant with respect to the action of the positive loop group. We show this is a symmetric monoidal category, and then we apply a Tannakian formalism to show this category is equivalent to the category of representations of a certain affine monoid scheme. We also show that our work provides a geometrization of the inverse of the mod $p$ Satake isomorphism. Along the way we prove that affine Schubert varieties are globally $F$-regular and we apply Frobenius splitting techniques to the theory of perverse $\mathbb{F}_p$-sheaves. Comment: Final version |
Databáze: | arXiv |
Externí odkaz: |