English
Related papers

Related papers: Complex nilmanifolds with constant holomorphic sec…

200 papers

On a compact K\"ahler manifold, we introduce a notion of almost nonpositivity for the holomorphic sectional curvature, which by definition is weaker than the existence of a K\"ahler metric with semi-negative holomorphic sectional curvature.…

Differential Geometry · Mathematics 2020-11-12 Yashan Zhang

For compact K\"ahlerian manifolds, the holomorphic pseudosymmetry reduces to the local symmetry if additionally the scalar curvature is constant and the structure function is non-negative. Similarly, the holomorphic Ricci-pseudosymmetry…

Differential Geometry · Mathematics 2010-11-18 Zbigniew Olszak

In this paper, we first establish several theorems about the estimation of distance function on real and strongly convex complex Finsler manifolds and then obtain a Schwarz lemma from a strongly convex weakly K\"ahler-Finsler manifold into…

Differential Geometry · Mathematics 2022-08-03 Jun Nie , Chunping Zhong

In this paper, we study numerically flat holomorphic vector bundles over a compact non-K\"ahler manifold $(X, \omega)$ with the Hermitian metric $\omega$ satisfying the Gauduchon and Astheno-K\"ahler conditions. We prove that numerically…

Differential Geometry · Mathematics 2019-02-26 Chao Li , Yanci Nie , Xi Zhang

In this paper we develop an analogue of the Berkovich analytification for non-necessarily algebraic complex spaces. We apply this theory to generalize to arbitrary compact K\"ahler manifolds a result of Chi Li, proving that a stronger…

Differential Geometry · Mathematics 2025-09-22 Pietro Mesquita-Piccione

We show a closed Bach-flat Riemannian manifold with a fixed positive constant scalar curvature has to be locally spherical if its Weyl and traceless Ricci tensors are small in the sense of either $L^\infty$ or $L^{\frac{n}{2}}$-norm.…

Differential Geometry · Mathematics 2017-04-24 Yi Fang , Wei Yuan

We show that a compact quaternionic-K\"ahler manifold with positive scalar curvature and nonnegative sectional curvature is isometric to a symmetric space. This extends a classical theorem of Berger.

Differential Geometry · Mathematics 2025-06-30 S. Brendle , U. Semmelmann

Given a compact K\"ahler manifold $X$ it is interesting to ask whether it admits a constant scalar curvature K\"ahler (cscK) metric. In this short note we show that there always exist cscK metrics on compact K\"ahler manifolds with nef…

Differential Geometry · Mathematics 2020-12-01 Zakarias Sjöström Dyrefelt

We study Hermitian metrics with constant second scalar curvature on compact manifolds. We first consider a Yamabe-type problem for the second Bismut scalar curvature under a natural topological condition, and then analyze elliptic equations…

Differential Geometry · Mathematics 2026-01-29 Liangdi Zhang

In this article we study compact K\ahler manifolds satisfying a certain nonnegativity condition on the bisectional curvature. Under this condition, we show that the scalar curvature is nonnegative and that the first Chern class is positive…

Differential Geometry · Mathematics 2011-09-01 Albert Chau , Luen-Fai Tam

On a Kahler manifold there is a clear connection between the complex geometry and underlying Riemannian geometry. In some ways, this can be used to characterize the Kahler condition. While such a link is not so obvious in the non-Kahler…

Differential Geometry · Mathematics 2016-06-23 Michael G. Dabkowski , Michael T. Lock

We prove that a product complex manifold cannot admit a complete K\"ahler metric with sectional curvature $K<c<0$ and Ricci curvature $Ric > d$, where $c$ and $d$ are constants. In particular, a product domain in $\C$ cannot cover a compact…

Differential Geometry · Mathematics 2007-05-23 Harish Seshadri

In this paper, we establish Chern number identities on compact complex surfaces. As an application, we prove that if $(M,g)$ is a compact Riemannian four-manifold with constant scalar curvature and admits a compatible complex structure $J$…

Differential Geometry · Mathematics 2025-08-18 Xiaokui Yang

We construct new explicit compact supersymmetric valid solutions with non-zero field strength, non-flat instanton and constant dilaton to the heterotic equations of motion in dimension six. We present balanced Hermitian structures on…

Differential Geometry · Mathematics 2009-11-13 Marisa Fernández , Stefan Ivanov , Luis Ugarte , Raquel Villacampa

The aim of this paper is to classify compact Kahler manifolds with quasi-constant holomorphic sectional curvature.

Differential Geometry · Mathematics 2016-02-26 Wlodzimierz Jelonek

A Hermitian-symplectic metric is a Hermitian metric whose K\"ahler form is given by the $(1,1)$-part of a closed $2$-form. Streets-Tian Conjecture states that a compact complex manifold admitting a Hermitian-symplectic metric must be…

Differential Geometry · Mathematics 2025-04-07 Yuqin Guo , Fangyang Zheng

The various scalar curvatures on an almost Hermitian manifold are studied, in particular with respect to conformal variations. We show several integrability theorems, which state that two of these can only agree in the K\"ahler case. Our…

Differential Geometry · Mathematics 2017-03-07 Mehdi Lejmi , Markus Upmeier

It is proved that if an almost Hermitian manifold of dimension greater than 4 has vanishing (classical) Bochner curvature tensor and is not Kaehlerian at a point, then it is flat in a neighbourhood of this point.

Differential Geometry · Mathematics 2011-08-31 Ognian Kassabov

We show that an $n$-dimensional Riemannian manifold with $n$-nonnegative or $n$-nonpositive curvature operator of the second kind has restricted holonomy $SO(n)$ or is flat. The result does not depend on completeness and can be improved…

Differential Geometry · Mathematics 2024-10-04 Jan Nienhaus , Peter Petersen , Matthias Wink , William Wylie

In this paper, we investigate the problem of prescribing Chern scalar curvatures on compact Hermitian manifolds with negative Gauduchon degree. By studying the convergence of the associated geometric flow, we obtain some existence results…

Differential Geometry · Mathematics 2023-04-19 Weike Yu