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arXiv · 0707.4140

Non-annulation effective et positivité locale des fibrés en droites amples adjoints

Amaël Broustet
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Abstract

We prove that Seshadri constants of some ample divisors are bigger than 1 on smooth threefolds whose anticanonical bundle is nef or on Fano varieties of small coindice. The main tools are (some known cases of) the Kawamata's effective non-vanishing conjecture and the adjunction theory. We prove the non-vanishing conjecture in dimension 3 in the case of line bundles of "high" volume using Kawamata's subadjunction formula.

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BibTeXRIS

Amaël Broustet. 2007-10-15. Non-annulation effective et positivité locale des fibrés en droites amples adjoints. https://arxiv.org/abs/0707.4140

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