On subvarieties with ample normal bundle

  title={On subvarieties with ample normal bundle},
  author={John Christian Ottem},
  journal={arXiv: Algebraic Geometry},
  • J. C. Ottem
  • Published 9 September 2013
  • Mathematics
  • arXiv: Algebraic Geometry
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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