English

Values of Harmonic Weak Maass forms on Hecke orbits

Number Theory 2018-12-05 v1

Abstract

Let q:=e2πizq:=e^{2 \pi iz}, where zHz \in \mathbb{H}. For an even integer kk, let f(z):=qhm=1(1qm)c(m)f(z):=q^h\prod_{m=1}^{\infty}(1-q^m)^{c(m)} be a meromorphic modular form of weight kk on Γ0(N)\Gamma_0(N). For a positive integer mm, let TmT_m be the mmth Hecke operator and DD be a divisor of a modular curve with level NN. Both subjects, the exponents c(m)c(m) of a modular form and the distribution of the points in the support of Tm.DT_m. D, have been widely investigated. When the level NN is one, Bruinier, Kohnen, and Ono obtained, in terms of the values of jj-invariant function, identities between the exponents c(m)c(m) of a modular form and the points in the support of Tm.DT_m.D. In this paper, we extend this result to general Γ0(N)\Gamma_0(N) in terms of values of harmonic weak Maass forms of weight 00. By the distribution of Hecke points, this applies to obtain an asymptotic behaviour of convolutions of sums of divisors of an integer and sums of exponents of a modular form.

Keywords

Cite

@article{arxiv.1812.01326,
  title  = {Values of Harmonic Weak Maass forms on Hecke orbits},
  author = {Dohoon Choi and Min Lee and Subong Lim},
  journal= {arXiv preprint arXiv:1812.01326},
  year   = {2018}
}
R2 v1 2026-06-23T06:30:50.368Z