The topological Breuil-M\'ezard conjecture for classical groups

Zhongyipan Lin

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arXiv · 2508.19722

The topological Breuil-M\'ezard conjecture for classical groups

Zhongyipan Lin

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Abstract

For unitary, orthogonal and symplectic groups, we compute the dimension of the reduced Emerton-Gee stacks, and give an explicit description of their top-dimensional Chow group. Our results are unconditional when $p\neq 2$. The main innovation is a new method for analyzing the vanishing locus of Galois cup products valued in high dimensions.

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Zhongyipan Lin. 2025-08-27. The topological Breuil-M\'ezard conjecture for classical groups. https://arxiv.org/abs/2508.19722

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