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arXiv · 1812.05024

Effective divisors in the projectivized Hodge bundle

Iulia Gheorghita
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Abstract

We compute the class of the closure of the locus of canonical divisors in the projectivization of the Hodge bundle $\mathbb{P}\overline{\mathcal{H}}_g$ over $\overline{\mathcal{M}}_g$ which have a zero at a Weierstrass point. We also show that the strata of canonical and bicanonical divisors with a double zero span extremal rays of the respective pseudoeffective cones.

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Iulia Gheorghita. 2018-12-12. Effective divisors in the projectivized Hodge bundle. https://arxiv.org/abs/1812.05024

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