Torsion in the Coherent Cohomology of Shimura Varieties and Galois Representations

George Boxer

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arXiv · 1507.05922

Torsion in the Coherent Cohomology of Shimura Varieties and Galois Representations

George Boxer

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Abstract

We introduce a method for producing congruences between Hecke eigenclasses, possibly torsion, in the coherent cohomology of automorphic vector bundles on certain good reduction Shimura varieties. The congruences are produced using some "generalized Hasse invariants" adapted to the Ekedahl-Oort stratification of the special fiber.

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George Boxer. 2015-07-21. Torsion in the Coherent Cohomology of Shimura Varieties and Galois Representations. https://arxiv.org/abs/1507.05922

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