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arXiv · 1402.1795

Irreducibility of Newton strata in GU(1,n-1) Shimura varieties

Jeff Achter
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Abstract

Let L be a quadratic imaginary field, inert at the rational prime p. Fix an integer n at least 3, and let M be the moduli space (in characteristic p) of principally polarized abelian varieties of dimension n equipped with an action by O_L of signature of (1,n-1). We show that each Newton stratum of M, other than the supersingular stratum, is irreducible.

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Jeff Achter. 2014-02-07. Irreducibility of Newton strata in GU(1,n-1) Shimura varieties. https://doi.org/10.1090/s2330-1511-2014-00011-0

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