PreprintarXiv licencearXiv
Homological branching laws for p-adic and mod p representations of GL2 over a p-adic field
Abstract
Let F be a finite extension of ℚp and p≥ 5. In this paper, we establish homological branching laws for mod p representations of GL2(F) restricted to split and nonsplit maximal tori, treating principal and special series and, when F=ℚp, supersingular representations. We determine the derived Hom-complexes in both orders for nonexceptional characters. At exceptional characters, we calculate their Euler--Poincaré characteristics under a p-torsion-freeness hypothesis. We also establish corresponding results for a class of unitary Banach space representations.
Related
- On multilinear forms for mod p representations of GL2 over a p-adic field
- $2$-adic Representations of Elliptic Curves over ℚ2
- On the existence of nonadmissible irreducible smooth representations of p-adic GLn
- On unitary representations of p-adic Sp2n and SO2n+1 of purely bad parity
- Local Converse Theorems for k-Middle Supercuspidal Representations of p-adic GL(kn)
BibTeX
@misc{chen2026homological,
title = {{Homological branching laws for $p$-adic and mod $p$ representations of $\rm GL_2$ over a $p$-adic field}},
author = {Yang Chen and Haoran Wang},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.29629},
eprint = {2610.29629},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.29629},
}
RIS
TY - UNPB
TI - Homological branching laws for p-adic and mod p representations of GL_2 over a p-adic field
AU - Yang Chen
AU - Haoran Wang
PY - 2026
DA - 2026/10/21
PB - arXiv
DO - 10.48550/arxiv.2610.29629
UR - https://arxiv.org/abs/2610.29629
AB - Let F be a finite extension of ℚ_p and p≥ 5. In this paper, we establish homological branching laws for mod p representations of GL_2(F) restricted to split and nonsplit maximal tori, treating principal and special series and, when F=ℚ_p, supersingular representations. We determine the derived Hom-complexes in both orders for nonexceptional characters. At exceptional characters, we calculate their Euler--Poincaré characteristics under a p-torsion-freeness hypothesis. We also establish corresponding results for a class of unitary Banach space representations.
ER -