English

Andreotti-Mayer loci and the Schottky problem

Algebraic Geometry 2007-05-23 v1

Abstract

We prove a lower bound for the codimension of the Andreotti-Mayer locus N_{g,1} and show that the lower bound is reached only for the hyperelliptic locus in genus 4 and the Jacobian locus in genus 5. In relation with the boundary of the Andreotti-Mayer loci we study subvarieties of principally polarized abelian varieties (B,Theta) parametrizing points b such that Theta and the translate Theta_b are tangentially degenerate along a variety of a given dimension.

Cite

@article{arxiv.math/0701353,
  title  = {Andreotti-Mayer loci and the Schottky problem},
  author = {Ciro Ciliberto and Gerard van der Geer},
  journal= {arXiv preprint arXiv:math/0701353},
  year   = {2007}
}

Comments

46 pages, Latex