English

RC-positive metrics on rationally connected manifolds

Algebraic Geometry 2020-11-18 v2 Complex Variables Differential Geometry

Abstract

In this paper, we prove that if a compact K\"ahler manifold XX has a smooth Hermitian metric ω\omega such that (TX,ω)(T_X,\omega) is uniformly RC-positive, then XX is projective and rationally connected. Conversely, we show that, if a projective manifold XX is rationally connected, then the tautological line bundle OTX(1)\mathscr{O}_{T_X^*}(-1) is uniformly RC-positive (which is equivalent to the existence of some RC-positive complex Finlser metric on XX). As an application, we prove that if (X,ω)(X,\omega) is a compact K\"ahler manifold with certain quasi-positive holomorphic sectional curvature, then XX is projective and rationally connected.

Keywords

Cite

@article{arxiv.1807.03510,
  title  = {RC-positive metrics on rationally connected manifolds},
  author = {Xiaokui Yang},
  journal= {arXiv preprint arXiv:1807.03510},
  year   = {2020}
}