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Special rays in the Mori cone of a projective variety

Published online by Cambridge University Press:  22 January 2016

Marco Andreatta  and
Gianluca Occhetta
Marco Andreatta
Affiliation:
Dipartimento di Matematica, Università degli Studi di Trento, Via Sommarive 14, I-38100 Povo (TN), ITALY, andreatt@science.unitn.it
Gianluca Occhetta
Affiliation:
Dipartimento di Matematica, Università degli Studi di Trento, Via Sommarive 14, I-38100 Povo (TN), ITALY, occhetta@science.unitn.it
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Abstract

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Let X be a smooth n-dimensional projective variety over an algebraically closed field k such that KX 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 Char(k) = 0 we also characterize non nef rays of length n – 2.

Keywords

14E3014J40
Type
Research Article
Information
Nagoya Mathematical Journal , Volume 168 , 2002 , pp. 127 - 137
Copyright
Copyright © Editorial Board of Nagoya Mathematical Journal 2002

References

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