English

Nef line bundles over finite fields

Algebraic Geometry 2015-03-24 v1 Commutative Algebra Number Theory

Abstract

We use Totaro's examples of non-semiample nef line bundles on smooth projective surfaces over finite fields to construct nef line bundles for which the first cohomology group cannot be killed by any generically finite covers. This is used to show a similar example of a nef and big line bundle on a smooth projective threefold over a finite field. This improves some examples of Bhatt and answers some of his questions. Finally, we prove a new vanishing theorem for the first cohomology group of strictly nef line bundles on projective varieties defined over finite fields.

Keywords

Cite

@article{arxiv.1111.6259,
  title  = {Nef line bundles over finite fields},
  author = {Adrian Langer},
  journal= {arXiv preprint arXiv:1111.6259},
  year   = {2015}
}

Comments

15 pages

R2 v1 2026-06-21T19:42:07.300Z