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Local Models in the ramified case. III. Unitary groups

G. Pappas·M. Rapoport
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Abstract

We continue our study of the reduction of PEL Shimura varieties with parahoric level structure at primes p at which the group that defines the Shimura variety ramifies. We describe "good" $p$-adic integral models of these Shimura varieties and study their 'etale local structure. In this paper we mainly concentrate on the case of unitary groups for a ramified quadratic extension. Some of our results are applications of the theory of twisted affine flag varieties in our previous paper math.AG/0607130.

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G. Pappas, M. Rapoport. 2007-02-10. Local Models in the ramified case. III. Unitary groups. https://arxiv.org/abs/math/0702286

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