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arXiv · 2204.10121

Hodge stratification in low dimension

Stéphane Bijakowski
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Abstract

We define and study the Hodge stratification for the special fiber of Shimura varieties defined with the Pappas-Rapoport condition, in the case of low ramification index ($e \leq 3$). For $e \leq 2$, the Hodge polygon induces a strong stratification. For $e=3$, one needs to introduce several polygons. They describe the isomorphism class of the sheaf of differentials with extra structure, and induce a strong stratification on the variety.

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Stéphane Bijakowski. 2022-04-21. Hodge stratification in low dimension. https://arxiv.org/abs/2204.10121

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