arXiv 0804.10232008-04-07math.AGmath.CV

Submanifolds with ample normal bundles and a conjecture of Hartshorne

Thomas Peternell

备注：: 14 pages

英文摘要：

The Hartshorne conjecture predicts that two submanifolds X and Y in a projective manifold Z with ample normal bundles meets as soon as dim X + dim Y is at least dim Z. We mostly assume slightly stronger that one of the normal bundles is positive in the sense of Griffiths. We observe that the conjecture holds generically, relate it to question on cones of cycles and verify it in various cases.

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