English

A partial converse to the Andreotti-Grauert theorem

Algebraic Geometry 2019-02-20 v2 Complex Variables Differential Geometry

Abstract

Let XX be a smooth projective manifold with dimCX=n\dim_\mathbb{C} X=n. We show that if a line bundle LL is (n1)(n-1)-ample, then it is (n1)(n-1)-positive. This is a partial converse to the Andreotti-Grauert theorem. As an application, we show that a projective manifold XX is uniruled if and only if there exists a Hermitian metric ω\omega on XX such that its Ricci curvature Ric(ω)\mathrm{Ric}(\omega) has at least one positive eigenvalue everywhere.

Keywords

Cite

@article{arxiv.1707.08006,
  title  = {A partial converse to the Andreotti-Grauert theorem},
  author = {Xiaokui Yang},
  journal= {arXiv preprint arXiv:1707.08006},
  year   = {2019}
}
R2 v1 2026-06-22T20:56:54.643Z