Abstract
We show how to use effective non-vanishing to 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. We prove the effective non-vanishing conjecture of Ionescu–Kawamata in dimension 3 in the case of line bundles of “high” volume.
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Broustet, A. Non-annulation effective et positivité locale des fibrés en droites amples adjoints. Math. Ann. 343, 727–755 (2009). https://doi.org/10.1007/s00208-008-0272-x
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DOI: https://doi.org/10.1007/s00208-008-0272-x