English

Mirror symmetry and the Breuil-M\'ezard Conjecture

Number Theory 2025-07-18 v4 Algebraic Geometry Representation Theory

Abstract

The Breuil-M\'{e}zard Conjecture predicts the existence of hypothetical "Breuil-Mezard cycles" in the moduli space of mod pp Galois representations of Gal(Qq/Qq)\mathrm{Gal}(\overline{\mathbb{Q}}_q/\mathbb{Q}_q) that should govern congruences between mod pp automorphic forms. For generic parameters, we propose a construction of Breuil-M\'{e}zard cycles in arbitrary rank, and verify that they satisfy the Breuil-M\'{e}zard Conjecture for all sufficiently generic tame types and small Hodge-Tate weights. Our method is purely local and group-theoretic, and completely distinct from previous approaches to the Breuil-M\'ezard Conjecture. In particular, we leverage new connections between the Breuil-M\'ezard Conjecture and phenomena occurring in homological mirror symmetry and geometric representation theory.

Keywords

Cite

@article{arxiv.2310.07006,
  title  = {Mirror symmetry and the Breuil-M\'ezard Conjecture},
  author = {Tony Feng and Bao Le Hung},
  journal= {arXiv preprint arXiv:2310.07006},
  year   = {2025}
}

Comments

This version improves significantly over the previous one, generalizing the results to essentially arbitrary unramified groups (see Section 1.5 for discussion of changes). Includes a new appendix written jointly with Zhongyipan Lin