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arXiv · 1107.4878

Minimal Model Program with scaling and adjunction theory

Marco Andreatta
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Abstract

Let (X,L) be a quasi polarized pairs, i.e. X is a normal complex projective variety and L is a nef and big line bundle on it. We study, up to birational equivalence, the positivity (nefness) of the adjoint bundles K_X + rL for high rational number r. For this we run a Minimal Model Program with scaling relative to the divisor K_X +rL. We give some applications, namely the classification up to birational equivalence of quasi polarized pairs with sectional genus 0,1 and of embedded projective varieties X < P^N with degree smaller than 2codim(X) +2.

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Marco Andreatta. 2011-07-25. Minimal Model Program with scaling and adjunction theory. https://arxiv.org/abs/1107.4878

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