English

On the projective fourfolds with almost numerically positive canonical divisors

Algebraic Geometry 2007-05-23 v7

Abstract

Let XX be a four-dimensional projective variety defined over the field of complex numbers with only terminal singularities. We prove that if the intersection number of the canonical divisor KK with every very general curve is positive (KK is almost numerically positive) then every very general proper subvariety of XX is of general type in the viewpoint of geometric Kodaira dimension. We note that the converse does not hold for simple abelian varieties.

Keywords

Cite

@article{arxiv.math/0409078,
  title  = {On the projective fourfolds with almost numerically positive canonical divisors},
  author = {Shigetaka Fukuda},
  journal= {arXiv preprint arXiv:math/0409078},
  year   = {2007}
}

Comments

9 pages, LaTeX2e; with minor changes

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