AMPLE SUBVARIETIES AND q-AMPLE DIVISORS

نویسنده

  • JOHN CHRISTIAN OTTEM
چکیده

We introduce a notion of ampleness for subschemes of any codimension using the theory of q-ample line bundles. We also investigate certain geometric properties satisfied by ample subvarieties, e.g. the Lefschetz hyperplane theorems and numerical positivity. Using these properties, we also construct a counterexample to the converse of the Andreotti-Grauert vanishing theorem.

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تاریخ انتشار 2014