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arXiv · 0802.3260

Supersingular Kottwitz-Rapoport strata and Deligne-Lusztig varieties

Ulrich Goertz·Chia-Fu Yu
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Abstract

We investigate Siegel modular varieties in positive characteristic with Iwahori level structure. On these spaces, we have the Newton stratification, and the Kottwitz-Rapoport stratification; one would like to understand how these stratifications are related to each other. We give a simple description of all KR strata which are entirely contained in the supersingular locus as disjoint unions of Deligne-Lusztig varieties. We also give an explicit numerical description of the KR stratification in terms of abelian varieties.

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BibTeXRIS

Ulrich Goertz, Chia-Fu Yu. 2008-07-10. Supersingular Kottwitz-Rapoport strata and Deligne-Lusztig varieties. https://arxiv.org/abs/0802.3260

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