English

Graded rings of paramodular forms of levels $5$ and $7$

Number Theory 2020-03-17 v2

Abstract

We compute generators and relations for the graded rings of paramodular forms of degree two and levels 5 and 7. The generators are expressed as quotients of Gritsenko lifts and Borcherds products. The computation is made possible by a characterization of modular forms on the Humbert surfaces of discriminant 4 that arise from paramodular forms by restriction.

Keywords

Cite

@article{arxiv.1904.10201,
  title  = {Graded rings of paramodular forms of levels $5$ and $7$},
  author = {Brandon Williams},
  journal= {arXiv preprint arXiv:1904.10201},
  year   = {2020}
}

Comments

22 pages. Minor corrections