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arXiv · 2505.08911

On the basic locus of GSpin Shimura varieties with vertex stabilizer level

Qiao He·Rong Zhou
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Abstract

We study the basic locus of Shimura varieties associated to the group of spinor similitudes of a quadratic space over $\mathbb{Q}$ with level structure given by the stabilizer of a vertex lattice. We give a description of the underlying reduced scheme of the associated Rapoport--Zink space, generalizing results of Howard--Pappas [HP17] and Oki [Oki20b], in the case of self-dual, and almost self dual level structure.

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Qiao He, Rong Zhou. 2025-05-13. On the basic locus of GSpin Shimura varieties with vertex stabilizer level. https://arxiv.org/abs/2505.08911

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