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Related papers: K\"ahler manifolds and mixed curvature

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In this paper we show an abundance of complete K\"ahler metrics with negative holomorphic bisectional curvature on total spaces of certain vector bundles. Assume that such total spaces are endowed with a wider class of nonpositively curved…

Differential Geometry · Mathematics 2025-11-18 Hanyu Wu , Bo Yang

We consider complete K\"ahler manifolds with nonnegative Ricci curvature. The main results are: 1. When the manifold has nonnegative bisectional curvature, we show that $\lim\limits_{r\to\infty}\frac{r^{2}}{vol(B(p, r))}\int_{B(p, r)}S$…

Differential Geometry · Mathematics 2024-04-15 Gang Liu

Given a projective or compact K\"ahler manifold X and a (smooth) hypersurface Y, we study conditions under which $X \setminus Y$ could be Stein. We apply this in particular to the case when X is the projectivization of the so-called…

Algebraic Geometry · Mathematics 2021-11-08 Andreas Höring , Thomas Peternell

In this work, we show that along a particular choice of Hermitian curvature flow, the non-positivity of Chern-Ricci curvature will be preserved if the initial metric has non-positive bisectional curvature. As an application, we show that…

Differential Geometry · Mathematics 2020-05-28 Man-Chun Lee

We study the structure of the Albanese map for K\"ahler manifolds with nef anticanonical bundle. First, we give a result for fourfolds whose Albanse torus is an elliptic curve. In the general case of any dimension, we look at two cases: The…

Algebraic Geometry · Mathematics 2024-02-22 Philipp Naumann , Xiaojun Wu

We show that if $M = X \times Y$ is the product of two complex manifolds (of positive dimensions), then $M$ does not admit any complete K\"ahler metric with bisectional curvature bounded between two negative constants. More generally, a…

Differential Geometry · Mathematics 2008-01-03 Harish Seshadri , Fangyang Zheng

We solve Teissier's proportionality problem for transcendental nef classes over a compact K\"ahler manifold which says that the equality in the Khovanskii-Teissier inequalities hold for two nef and big classes if and only if the two classes…

Algebraic Geometry · Mathematics 2014-10-21 Jixiang Fu , Jian Xiao

The goal of this work is to pursue the study of pseudo-effective line bundles and vector bundles. Our first result is a generalization of the Hard Lefschetz theorem for cohomology with values in a pseudo-effective line bundle. The Lefschetz…

Algebraic Geometry · Mathematics 2007-05-23 Jean-Pierre Demailly , Thomas Peternell , Michael Schneider

In this paper, we show that every harmonic map from a compact K\"ahler manifold with uniformly RC-positive curvature to a Riemannian manifold with non-positive complex sectional curvature is constant. In particular, there is no non-constant…

Differential Geometry · Mathematics 2018-09-13 Jun Wang , Xiaokui Yang

This paper proves that the universal covering of a compact K\"{a}hler manifold with small positive sectional curvature in a certain sense is contractible.

Differential Geometry · Mathematics 2025-02-20 Yuguang Zhang

For all complex dimensions n>=2, we construct complete Kaehler manifolds of bounded curvature and non-negative Ricci curvature whose Kaehler--Ricci evolutions immediately acquire Ricci curvature of mixed sign.

Differential Geometry · Mathematics 2007-05-23 Dan Knopf

We show that for any solution to the K\"ahler-Ricci flow with positive bisectional curvature on a compact K\"ahler manifold $M^n$, the bisectional curvature has a uniform positive lower bound. As a consequence, the solution converges…

Differential Geometry · Mathematics 2010-03-29 Huai-Dong Cao , Meng Zhu

Given a surjective holomorphic map between two compact Kaehler manifolds, we investigate the positivity properties of relative adjoint transcendental classes which are inherited from similar fiberwise properties. As a consequence, we solve…

Complex Variables · Mathematics 2012-09-12 Mihai Paun

We study complete noncompact long time solutions $(M, g(t))$ to the K\"ahler-Ricci flow with uniformly bounded nonnegative holomorphic bisectional curvature. We will show that when the Ricci curvature is positive and uniformly pinched, i.e.…

Differential Geometry · Mathematics 2008-06-17 Albert Chau , Luen-Fai Tam

In this paper, we show that if the holomorphic tangent bundle $TX$ of a compact K\"ahler manifold $X$ is uniformly weakly RC-positive, then $X$ is projective and rationally connected. This result is previously established by Xiaokui Yang…

Differential Geometry · Mathematics 2026-04-08 Kuang-Ru Wu

We propose a new approach to the study of compact Riemannian manifolds with nonnegative Ricci curvature and strictly convex boundary or positive Ricci curvature and convex boundary. Several conjectures are formulated. Some partial results…

Differential Geometry · Mathematics 2020-05-27 Xiaodong Wang

In this short note, we prove the existence of constant scalar curvature K\"ahler metrics on compact K\"ahler manifolds with semi-ample canonical bundles.

Differential Geometry · Mathematics 2018-05-18 Wangjian Jian , Yalong Shi , Jian Song

Let $X$ be a complex manifold and $L$ be a holomorphic line bundle on $X$. Assume that $L$ is semi-positive, namely $L$ admits a smooth Hermitian metric with semi-positive Chern curvature. Let $Y$ be a compact K\"ahler submanifold of $X$…

Complex Variables · Mathematics 2020-03-09 Takayuki Koike

In this paper, we prove that a compact K\"ahler manifold $X$ with semi-positive holomorphic sectional curvature admits a locally trivial fibration $\phi \colon X \to Y$, where the fiber $F$ is a rationally connected projective manifold and…

Differential Geometry · Mathematics 2025-02-04 Shin-ichi Matsumura

We produce new examples of non-K\"ahler complete expanding gradient Ricci solitons on trivial vector bundles over a product of Einstein manifolds with positive scalar curvature.

Differential Geometry · Mathematics 2008-11-25 Andrew S. Dancer , McKenzie Y. Wang