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The supersingular loci and mass formulas on Siegel modular varieties

Chia-Fu Yu
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Abstract

We describe the supersingular locus of the Siegel 3-fold with a parahoric level structure. We also study its higher dimensional generalization. Using this correspondence and a deep result of Li and Oort, we evaluate the number of irreducible components of the supersingular locus of the Siegel moduli space $\calA_{g,1,N}$ for arbitrary $g$.

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Chia-Fu Yu. 2007-01-24. The supersingular loci and mass formulas on Siegel modular varieties. https://arxiv.org/abs/math/0608458

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