English

Shimura curves in the Prym loci of ramified double covers

Algebraic Geometry 2020-07-21 v1

Abstract

We study Shimura curves of PEL type in the space of polarised abelian varieties ApδA^{\delta}_p generically contained in the ramified Prym locus. We generalise to ramified double covers, the construction done in [10] in the unramified case and in the case of two ramification points. Namely, we construct families of double covers which are compatible with a fixed group action on the base curve. We only consider the case of one-dimensional families and where the quotient of the base curve by the group is P1{\mathbb P}^1. Using computer algebra we obtain 184 Shimura curves contained in the (ramified) Prym loci.

Keywords

Cite

@article{arxiv.2007.09646,
  title  = {Shimura curves in the Prym loci of ramified double covers},
  author = {Paola Frediani and Gian Paolo Grosselli},
  journal= {arXiv preprint arXiv:2007.09646},
  year   = {2020}
}