English

Hodge filtration and crystalline representations of $\mathrm{GL}_n$

Number Theory 2025-12-16 v1 Representation Theory

Abstract

Let pp be a prime number, nn an integer 2\geq 2 and ρ\rho an nn-dimensional automorphic pp-adic Galois representation (for a compact unitary group) such that r:=ρGal(Qp/Qp)r:=\rho\vert_{\mathrm{Gal}(\overline{\mathbb{Q}_p}/\mathbb{Q}_p)} is crystalline. Under a mild assumption on the Frobenius eigenvalues of D:=Dcris(r)D:=D_{\mathrm{cris}}(r) and under the usual Taylor-Wiles conditions, we show that the locally analytic representation of GLn(Qp)\mathrm{GL}_n(\mathbb{Q}_p) associated to ρ\rho in the corresponding Hecke eigenspace of the completed H0H^0 contains an explicit finite length subrepresentation which determines and only depends on rr. This generalizes previous results of the second author which assumed that the Hodge filtration on DD was as generic as possible. Our approach provides a much more explicit link to this Hodge filtration (in all cases), which allows to study the internal structure of this finite length locally analytic subrepresentation.

Keywords

Cite

@article{arxiv.2512.12153,
  title  = {Hodge filtration and crystalline representations of $\mathrm{GL}_n$},
  author = {Christophe Breuil and Yiwen Ding},
  journal= {arXiv preprint arXiv:2512.12153},
  year   = {2025}
}

Comments

135 pages, with an appendix by Zhixiang Wu