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arXiv · 0708.4188

Rational maps between moduli spaces of curves and Gieseker-Petri divisors

Gavril Farkas
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Abstract

We perform an intersection theoretic study of the rational map between two different moduli spaces of stable curves which associates to a curve its corresponding Brill-Noether locus (in the case this locus has virtual dimension 1). We then use these results to describe the cone of moving divisors on M_g. Several other applications to moduli spaces of Prym varieties are presented. In a different direction, we prove that the locus in M_g of curves failing to satisfy the Gieseker-Petri theorem is supported in codimension 1 for every possible type of linear series.

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Gavril Farkas. 2009-05-09. Rational maps between moduli spaces of curves and Gieseker-Petri divisors. https://arxiv.org/abs/0708.4188

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