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arXiv · 2408.07953

Geometric Casselman-Shalika in mixed characteristic

Ashwin Iyengar·Milton Lin·Konrad Zou
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Abstract

We establish a geometric analog of the Casselman-Shalika formula for a split connected reductive group over a mixed characteristic local field. In particular, we construct sheaves on the Witt vector affine Grassmannian which geometrize the Fourier coefficients of spherical Hecke operators, and compute their cohomology.

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Ashwin Iyengar, Milton Lin, Konrad Zou. 2024-08-15. Geometric Casselman-Shalika in mixed characteristic. https://arxiv.org/abs/2408.07953

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