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arXiv · 1305.2244

On the singularities of effective loci of line bundles

Lei Song
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Abstract

We prove that every irreducible component of semi-regular loci of effective line bundles in the Picard scheme of a smooth projective variety has at worst rational singularities. This generalizes Kempf's result on rational singularities of $W^0_d$ for smooth curves. We also work out an example of such loci for a ruled surface.

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Lei Song. 2013-05-10. On the singularities of effective loci of line bundles. https://arxiv.org/abs/1305.2244

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