English

Rankin-Cohen Brackets of Hilbert Hecke Eigenforms

Number Theory 2024-05-29 v1

Abstract

Over any fixed totally real number field with narrow class number one, we prove that the Rankin-Cohen bracket of two Hecke eigenforms for the Hilbert modular group can only be a Hecke eigenform for dimension reasons, except for a couple of cases where the Rankin-Selberg method does not apply. We shall also prove a conjecture of Freitag on the volume of Hilbert modular groups, and assuming a conjecture of Freitag on the dimension of the cuspform space, we obtain a finiteness result on eigenform product identities.

Keywords

Cite

@article{arxiv.2405.17887,
  title  = {Rankin-Cohen Brackets of Hilbert Hecke Eigenforms},
  author = {Yichao Zhang and Yang Zhou},
  journal= {arXiv preprint arXiv:2405.17887},
  year   = {2024}
}
R2 v1 2026-06-28T16:43:22.714Z