English

On the proportion of locally soluble superelliptic curves

Number Theory 2025-09-17 v2

Abstract

We investigate the proportion of superelliptic curves that have a Qp\mathbb{Q}_p point for every place pp of Q\mathbb{Q}. We show that this proportion is positive and given by the product of local densities, we provide lower bounds for this proportion in general, and for superelliptic curves of the form y3=f(x,z)y^3 = f(x,z) for an integral binary form ff of degree 6, we determine this proportion to be 96.94%. More precisely, we give explicit rational functions in pp for the proportion of such curves over Zp\mathbb{Z}_p having a Qp\mathbb{Q}_p-point.

Keywords

Cite

@article{arxiv.2111.04697,
  title  = {On the proportion of locally soluble superelliptic curves},
  author = {Lea Beneish and Christopher Keyes},
  journal= {arXiv preprint arXiv:2111.04697},
  year   = {2025}
}

Comments

64 pages. Accepted for publication in Finite Fields and Their Applications