On the Prym map for cyclic covers of genus two curves

Fuente: arXiv
Gespeichert in:
Bibliographische Detailangaben
1. Verfasser: Agostini, Daniele
Format: Preprint
Veröffentlicht: 2020
Schlagworte:
Online-Zugang:
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
_version_ 1866914838078291968
author Agostini, Daniele
author_facet Agostini, Daniele
contents The Prym map assigns to each covering of curves a polarized abelian variety. In the case of unramified cyclic covers of curves of genus two, we show that the Prym map is ramified precisely on the locus of bielliptic covers. The key observation is that we can naturally associate to such a cover an abelian surface with a cyclic polarization, and then the codifferential of the Prym map can be interpreted in terms of multiplication of sections on the abelian surface. Furthermore, we give a different proof of a result by Ramanan that a genus two cyclic cover of degree sufficiently high is never hyperelliptic.
format Preprint
id arxiv_https___arxiv_org_abs_2001_06264
institution arXiv
publishDate 2020
record_format arxiv
spellingShingle On the Prym map for cyclic covers of genus two curves
Agostini, Daniele
Algebraic Geometry
The Prym map assigns to each covering of curves a polarized abelian variety. In the case of unramified cyclic covers of curves of genus two, we show that the Prym map is ramified precisely on the locus of bielliptic covers. The key observation is that we can naturally associate to such a cover an abelian surface with a cyclic polarization, and then the codifferential of the Prym map can be interpreted in terms of multiplication of sections on the abelian surface. Furthermore, we give a different proof of a result by Ramanan that a genus two cyclic cover of degree sufficiently high is never hyperelliptic.
title On the Prym map for cyclic covers of genus two curves
topic Algebraic Geometry
url https://arxiv.org/abs/2001.06264