Special rays in the Mori cone of a projective variety

Marco Andreatta; Gianluca Occhetta

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Special rays in the Mori cone of a projective variety

Marco Andreatta·Gianluca Occhetta

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Abstract

Let $X$ be a smooth $n$-dimensional projective variety over an algebraically closed field $k$ such that $K_X$ is not nef. We give a characterization of non nef extremal rays of $X$ of maximal length (i.e of length $n-1$); in the case of $\ch(k) = 0$ we also characterize non nef rays of length $n-2$.

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BibTeX RIS

Marco Andreatta, Gianluca Occhetta. 2000-10-11. Special rays in the Mori cone of a projective variety. https://arxiv.org/abs/math/0010101

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