English

Effective construction of Hilbert modular forms of half-integral weight

Number Theory 2022-10-14 v2

Abstract

Given a Hilbert cuspidal newform gg we construct a family of modular forms of half-integral weight whose Fourier coefficients give the central values of the twisted LL-series of gg by fundamental discriminants. The family is parametrized by quadratic conditions on the primes dividing the level of gg, where each form has coefficients supported on the discriminants satisfying the conditions. These modular forms are given as generalized theta series and thus their coefficients can be effectively computed. Our construction works over arbitrary totally real number fields, except that in the case of odd degree the square levels are excluded. It includes all discriminants except those divisible by primes whose square divides the level.

Keywords

Cite

@article{arxiv.2107.04483,
  title  = {Effective construction of Hilbert modular forms of half-integral weight},
  author = {Nicolás Sirolli and Gonzalo Tornaría},
  journal= {arXiv preprint arXiv:2107.04483},
  year   = {2022}
}

Comments

Final version, published in Mathematische Zeitschriften