Topological flatness of orthogonal spin local models

Jie Yang

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arXiv · 2512.16646

Topological flatness of orthogonal spin local models

Jie Yang

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Abstract

Let $p$ be an odd prime and $F$ be a complete discretely valued field with residue field of characteristic $p$. For any parahoric level structure of the split even orthogonal similitude group $\operatorname{GO}_{2n}$ over $F$, we prove a preliminary form of the Pappas-Rapoport flatness conjecture: the associated spin local model is topologically flat.

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Jie Yang. 2025-12-18. Topological flatness of orthogonal spin local models. https://arxiv.org/abs/2512.16646

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