Regular models of ramified unitary Shimura varieties at maximal parahoric level

2024/10/06 by He, Qiao, Luo, Yu, Shi, Yousheng · 2 citations
#Algebraic Geometry (math.AG) #FOS: Mathematics #Number Theory (math.NT)

paper · doi:10.48550/arxiv.2410.04500

Abstract

We use the idea of splitting models to define and study a semi-stable model for unitary Shimura varieties of signature (n-1,1) with maximal parahoric level structure at ramified primes. In this case, the ``naive'' splitting model defined by Pappas and Rapoport fails to be flat in a crucial way. We prove that the genuine splitting model in this case is flat with semi-stable reduction.

Cited by

• 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

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