Local Models in the ramified case. III. Unitary groups

2007/02/10 by G. Pappas, Pappas, G., Michael Rapoport +2 · 5 citations
Mathematics · #Advanced Algebra and Geometry #Algebraic Geometry (math.AG) #FOS: Mathematics #Geometry and complex manifolds #Number Theory (math.NT) #Spectral Theory in Mathematical Physics #math.AG #math.NT

paper · pdf · doi:10.48550/arxiv.math/0702286

57 pages, 5 figures

arxiv created 2007/02/10 · openalex publication_date 2007/02/10 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28

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.

Citations

• A guide to the reduction modulo p of Shimura varieties

Cited by

• On the flatness of spin local models for split even orthogonal groups
• Topological flatness of orthogonal spin local models
• The basic locus of regular ramified unitary Rapoport-Zink spaces at vertex-stabilizer level
• The basic locus of unitary splitting Rapoport-Zink spaces with vertex stabilizer level
• Arithmetic and Geometric Langlands Program

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