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arXiv · 1511.04097

On rationalizing divisors

Lorenzo Prelli
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Abstract

Rational pairs generalize the notion of rational singularities to reduced pairs $(X,D)$. In this paper we deal with the problem of determining whether a normal variety $X$ has a rationalizing divisor, i.e. a reduced divisor $D$ such that $(X, D)$ is a rational pair. We give a criterion for cones to have a rationalizing divisor, and relate the existence of such a divisor to the locus of rational singularities of a variety.

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Lorenzo Prelli. 2015-11-12. On rationalizing divisors. https://arxiv.org/abs/1511.04097

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