English

Inductive approach to effective b-semiampleness

Algebraic Geometry 2012-07-02 v1

Abstract

It has been conjectured by Prokhorov and Shokurov that the moduli part in the canonical bundle formula is effectively b-semiample. In this work we reduce this conjecture to the case where the base of the fibration has dimension one. Moreover, in the case where the moduli part M is numerically trivial, we prove the existence of an integer m, that depends only on the middle Betti number of a canonical covering of the fibre, such that mM is linearly equivalent to the trivial bundle.

Keywords

Cite

@article{arxiv.1206.6966,
  title  = {Inductive approach to effective b-semiampleness},
  author = {Enrica Floris},
  journal= {arXiv preprint arXiv:1206.6966},
  year   = {2012}
}

Comments

20 pages

R2 v1 2026-06-21T21:28:00.768Z