English

Subadjunction for quasi-log canonical pairs and its applications

Algebraic Geometry 2020-09-02 v3

Abstract

We establish a kind of subadjunction formula for quasi-log canonical pairs. As an application, we prove that a connected projective quasi-log canonical pair whose quasi-log canonical class is anti-ample is simply connected and rationally chain connected. We also supplement the cone theorem for quasi-log canonical pairs. More precisely, we prove that every negative extremal ray is spanned by a rational curve. Finally, we treat the notion of Mori hyperbolicity for quasi-log canonical pairs.

Keywords

Cite

@article{arxiv.2004.01036,
  title  = {Subadjunction for quasi-log canonical pairs and its applications},
  author = {Osamu Fujino},
  journal= {arXiv preprint arXiv:2004.01036},
  year   = {2020}
}

Comments

17 pages, very very minor modifications, v3: minor revisions following referee's comments