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arXiv · 2309.03371

The Ekedahl-Oort Stratification and the Semi-Module Stratification

Ryosuke Shimada
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Abstract

In this paper we compare the $\mathbb J$-stratification (or the semi-module stratification) and the Ekedahl-Oort stratification of affine Deligne-Lusztig varieties in the superbasic case. In particular, we classify the cases where the $\mathbb J$-stratification gives a refinement of the Ekedahl-Oort stratification, which include many interesting cases such that the affine Deligne-Lusztig variety admits a simple geometric structure.

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Ryosuke Shimada. 2023-09-06. The Ekedahl-Oort Stratification and the Semi-Module Stratification. https://arxiv.org/abs/2309.03371

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