English

Fourier coefficients of vector-valued modular forms of dimension 2

Number Theory 2019-08-15 v1

Abstract

We prove the following theorem. Suppose that F=(f1,f2)F=(f_1, f_2) is a 2-dimensional vector-valued modular form on SL2(Z)SL_2(Z) whose component functions f1,f2f_1, f_2 have rational Fourier coefficients with bounded denominators. Then f1f_1 and f2f_2 are classical modular forms on a congruence subgroup of the modular group.

Keywords

Cite

@article{arxiv.1304.4288,
  title  = {Fourier coefficients of vector-valued modular forms of dimension 2},
  author = {Cameron Franc and Geoffrey Mason},
  journal= {arXiv preprint arXiv:1304.4288},
  year   = {2019}
}