中文

On the Kleiman-Mori cone

代数几何 2007-05-23 v1

摘要

The Kleiman-Mori cone plays important roles in the birational geometry. In this paper, we construct complete varieties whose Kleiman-Mori cones have interesting properties. First, we construct a simple and explicit example of complete non-projective singular varieties for which Kleiman's ampleness criterion does not hold. More precisely, we construct a complete non-projective toric variety XX and a line bundle LL on XX such that LL is positive on NEˉ(X){0}\bar {NE}(X)\setminus \{0\}. Next, we construct complete singular varieties XX with NE(X)=N1(X)RkNE(X)=N_1(X)\simeq \mathbb R^k for any kk. These explicit examples seem to be missing in the literature.

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引用

@article{arxiv.math/0501055,
  title  = {On the Kleiman-Mori cone},
  author = {Osamu Fujino},
  journal= {arXiv preprint arXiv:math/0501055},
  year   = {2007}
}

备注

8 pages