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Irreducibility and p-adic monodromies on the Siegel moduli spaces

Chia-Fu Yu
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Abstract

We generalize the surjectivity result of the $p$-adic monodromy for the ordinary locus of a Siegel moduli space by Faltings and Chai (independently by Ekedahl) to that for any $p$-rank stratum. We discuss irreducibility and connectedness of some $p$-rank strata of the moduli spaces with parahoric level structure. Finer results are obtained on the Siegel 3-fold with Iwahori level structure.

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Chia-Fu Yu. 2008-02-13. Irreducibility and p-adic monodromies on the Siegel moduli spaces. https://arxiv.org/abs/math/0612839

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