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arXiv · 2003.04738

EKOR strata on Shimura varieties with parahoric reduction

Jens Hesse
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Abstract

We investigate the geometry of the special fiber of the integral model of a Shimura variety with parahoric level at a given prime place. To be more precise, we deal with the EKOR stratification which interpolates between the Ekedahl-Oort and Kottwitz-Rapoport stratifications. In the Siegel case we give a geometric description by suitably generalizing the theory of $G$-zips of Moonen, Wedhorn, Pink and Ziegler to our context.

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Jens Hesse. 2020-03-06. EKOR strata on Shimura varieties with parahoric reduction. https://arxiv.org/abs/2003.04738

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