A characterization of semiampleness and contractions of relative curves
Algebraic Geometry
2007-05-23 v2
Abstract
A line bundle with a base-point-free multiple is called semiample. I give a cohomological characterization of semiample line bundles. The result is a common generalization of the Fujita-Zariski criterion for semiampleness and the Grothendieck-Serre characterization of ampleness. Applying the Fujita-Zariski Theorem, I characterize contractible curves in 1-dimensional families.
Keywords
Cite
@article{arxiv.math/0001183,
title = {A characterization of semiampleness and contractions of relative curves},
author = {Stefan Schroeer},
journal= {arXiv preprint arXiv:math/0001183},
year = {2007}
}
Comments
6 pages. Minor changes. To appear in Kodai Math. J