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arXiv · 2409.11720

Systems of Hecke eigenvalues on subschemes of Shimura varieties

Stefan Reppen
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Abstract

We show that the systems of Hecke eigenvalues that appear in the coherent cohomology with coefficients in automorphic line bundles of any mod $p$ abelian type compact Shimura variety at hyperspecial level are the same as those appearing in any Hecke-equivariant closed subscheme. We also prove analogous results for noncompact Shimura varieties or nonclosed subschemes, such as Ekedahl-Oort strata, length strata and central leaves.

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Stefan Reppen. 2024-09-18. Systems of Hecke eigenvalues on subschemes of Shimura varieties. https://arxiv.org/abs/2409.11720

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