$(\varepsilon, \delta)$--Quasi-Negative Curvature and Positivity of the Canonical Bundle

Abstract

A recent theorem of Diverio--Trapani and Wu--Yau asserts that a compact K\"ahler manifold with a K\"ahler metric of quasi-negative holomorphic sectional curvature is projective and canonically polarized. This confirms a long-standing conjecture of Yau. We consider the notion of $(\varepsilon,\delta)$--quasi-negativity, generalizing quasi-negativity, and obtain gap-type theorems for $\int_X c_1(K_X)^n>0$ in terms of the real bisectional curvature and weighted orthogonal Ricci curvature. These theorems are also a generalization of that results in \cite{ZhangZheng} by Zhang-Zheng and in \cite{ChuLeeTam} by Chu-Lee-Tam.