English

Hasse invariant and group cohomology

Number Theory 2007-05-23 v1

Abstract

Let p be a prime number. The Hasse invariant is a modular form modulo p that is often used to produce congruences between modular forms of different weights. We show how to produce such congruences between forms of weights 2 and p+1, in terms of group cohomology. We also show how our method works in the contexts of quadratic imaginary fields (where there is no Hasse invariant available) and Hilbert modular forms over totally real fields of even degree.

Keywords

Cite

@article{arxiv.math/0210401,
  title  = {Hasse invariant and group cohomology},
  author = {Bas Edixhoven and Chandrashekhar Khare},
  journal= {arXiv preprint arXiv:math/0210401},
  year   = {2007}
}
R2 v1 2026-07-22T16:48:46.203Z