Special rays in the Mori cone of a projective variety

2000/10/11 by Marco Andreatta, Andreatta, Marco, Gianluca Occhetta +1 · 2 citations
Computer Science · Mathematics · #14E30 #14J40 #Algebraic Geometry (math.AG) #Algebraic Geometry and Number Theory #FOS: Mathematics #Meromorphic and Entire Functions #Polynomial and algebraic computation #math.AG #msc:14E30 #msc:14J40

paper · pdf · doi:10.48550/arxiv.math/0010101

9 pages

arxiv created 2000/10/11 · openalex publication_date 2000/10/11 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28

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.

Cited by

• Quotients of flag varieties and their birational geometry
• The geometry of Frobenius on toric varieties

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