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arXiv · 1309.2263

On subvarieties with ample normal bundle

John Christian Ottem
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Abstract

We show that a pseudoeffective R-divisor has numerical dimension 0 if it is numerically trivial on a subvariety with ample normal bundle. This implies that the cycle class of a curve with ample normal bundle is big, giving an affirmative answer to a question of Peternell. We also give other positivity properties such subvarieties.

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John Christian Ottem. 2013-12-04. On subvarieties with ample normal bundle. https://arxiv.org/abs/1309.2263

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