English

Gelfand-Kirillov dimension and mod p cohomology for GL2

Number Theory 2024-05-07 v7 Representation Theory

Abstract

Let pp be a prime number, FF a totally real number field unramified at places above pp and DD a quaternion algebra of center FF split at places above pp and at no more than one infinite place. Let vv be a fixed place of FF above pp and r:Gal(F/F)GL2(Fp)\overline{r} : {\rm Gal}(\overline F/F)\rightarrow \mathrm{GL}_2(\overline{\mathbb{F}}_p) an irreducible modular continuous Galois representation which, at the place vv, is semisimple and sufficiently generic (and satisfies some weak genericity conditions at a few other finite places). We prove that many of the admissible smooth representations of GL2(Fv)\mathrm{GL}_2(F_v) over Fp\overline{\mathbb{F}}_p associated to r\overline{r} in the corresponding Hecke-eigenspaces of the mod pp cohomology have Gelfand--Kirillov dimension [Fv:Q][F_v:\mathbb{Q}], as well as several related results.

Keywords

Cite

@article{arxiv.2009.03127,
  title  = {Gelfand-Kirillov dimension and mod p cohomology for GL2},
  author = {Christophe Breuil and Florian Herzig and Yongquan Hu and Stefano Morra and Benjamin Schraen},
  journal= {arXiv preprint arXiv:2009.03127},
  year   = {2024}
}

Comments

Final version, to appear in Inventiones Mathematicae