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Related papers: On the uniqueness of almost-Kaehler structures

200 papers

We prove that every Kaehler metric, whose potential is a function of the time-like distance in the flat Kaehler-Lorentz space, is of quasi-constant holomorphic sectional curvatures, satisfying certain conditions. This gives a local…

Differential Geometry · Mathematics 2007-06-07 Georgi Ganchev , Vesselka Mihova

We review basic facts on the structure of nearly K\"ahler manifolds, focussing in particular on the six-dimensional case. A self-contained proof that nearly K\"ahler six-manifolds are Einstein is given by combining different known results.…

Differential Geometry · Mathematics 2020-10-26 Giovanni Russo

We show that strictly stable components of Allen-Cahn minimal hypersurfaces always occur with multiplicity one. We also establish the uniqueness of solutions converging to nondegenerate hypersurfaces with multiplicity one. Our results work…

Differential Geometry · Mathematics 2022-03-10 Marco A. M. Guaraco , Fernando C. Marques , Andre Néves

Given a non compact semisimple Lie group $G$ we describe all homogeneous spaces $G/L$ carrying an invariant almost K\"ahler structure $(\omega,J)$. When $L$ is abelian and $G$ is of classical type, we classify all such spaces which are…

Differential Geometry · Mathematics 2018-12-07 Dmitri V. Alekseevsky , Fabio Podestà

Given a compact constant scalar curvature Kaehler orbifold, with nontrivial holomorphic vector fields, whose singularities admit a local ALE Kaehler Ricci-flat resolution, we find sufficient conditions on the position of the singular points…

Differential Geometry · Mathematics 2015-07-21 Claudio Arezzo , Riccardo Lena , Lorenzo Mazzieri

Indefinite Kaehler solutions of the Einstein equations are studied, and it is almost completely determined which compact complex surfaces admit such metrics.

dg-ga · Mathematics 2009-10-28 Jimmy Petean

For an almost contact metric manifold $N$, we find conditions for which either the total space of an $S^1$-bundle over $N$ or the Riemannian cone over $N$ admits a strong K\"ahler with torsion (SKT) structure. In this way we construct new…

Differential Geometry · Mathematics 2010-11-19 Marisa Fernandez , Anna Fino , Luis Ugarte , Raquel Villacampa

The purpose of this article is to study the existence and uniqueness of quasi-Einstein structures on $3$-dimensional homogeneous Riemannian manifolds. To this end, we use the eight model geometries for 3-dimensional manifolds identified by…

Differential Geometry · Mathematics 2014-05-23 A. Barros , E. Ribeiro , J. Silva Filho

The aim of this paper is to describe Kahler surfaces with quasi-constant holomorphic curvature

Differential Geometry · Mathematics 2017-06-26 Wlodzimierz Jelonek

We show that if a compact complex manifold admits a K\"ahler metric whose holomorphic sectional curvature is everywhere non positive and strictly negative in at least one point, then its canonical bundle is positive.

Differential Geometry · Mathematics 2018-07-19 Simone Diverio , Stefano Trapani

We use some natural lifts defined on the cotangent bundle T*M of a Riemannian manifold (M,g) in order to construct an almost Hermitian structure (G,J) of diagonal type. The obtained almost complex structure J on T*M is integrable if and…

Differential Geometry · Mathematics 2007-05-23 Vasile Oproiu , Dumitru Daniel Porosniuc

We consider singular quasilinear elliptic systems with homogeneous Dirichlet boundary condition. Using Leray-Schauder topological degree, combined with the sub-supersolutions method and suitable truncation arguments, we establish the…

Analysis of PDEs · Mathematics 2025-10-27 Nouredine Medjoudj , Abdelkrim Moussaoui

Tian initiated the study of incomplete K\"ahler-Einstein metrics on quasi-projective varieties with cone-edge type singularities along a divisor, described by the cone-angle $2\pi(1-\alpha)$ for $\alpha\in (0, 1)$. In this paper we study…

Differential Geometry · Mathematics 2015-01-30 Gabriele Di Cerbo , Luca F. Di Cerbo

We estimate $\delta$-invariants of some singular del Pezzo surfaces with quotient singularities, which we studied ten years ago. As a result, we show that each of these surfaces admits an orbifold K\"ahler--Einstein metric.

Algebraic Geometry · Mathematics 2020-01-22 Ivan Cheltsov , Jihun Park , Constantin Shramov

Hamiltonian stationary Lagrangian spheres in Kaehler-Einstein surfaces are minimal. We prove that in the family of non-Einstein Kaehler surfaces given by the product $\Sigma_1\times\Sigma_2$ of two complete orientable Riemannian surfaces of…

Differential Geometry · Mathematics 2012-12-04 Ildefonso Castro , Francisco Torralbo , Francisco Urbano

This paper is concerned with the existence of metrics of constant Hermitian scalar curvature on almost-K\"ahler manifolds obtained as smoothings of a constant scalar curvature K\"ahler orbifold, with $A_1$ singularities. More precisely,…

Differential Geometry · Mathematics 2018-06-21 Caroline Vernier

A compactness theorem is proved for a family of K\"{a}hler surfaces with constant scalar curvature and volume bounded from below, diameter bounded from above, Ricci curvature bounded and the signature bounded from below. Furthermore, a…

Differential Geometry · Mathematics 2013-04-04 Hongliang Shao

We construct an example of Ricci-flat almost-K\"ahler non-K\"ahler structure in four dimensions.

Differential Geometry · Mathematics 2009-10-31 PawełNurowski , Maciej Przanowski

Let (M,J) be a compact complex 2-manifold which which admits a Kaehler metric for which the integral of the scalar curvature is non-negative. Also suppose that M does not admit a Ricci-flat K\"ahler metric. Then if M is blown up at…

dg-ga · Mathematics 2008-02-03 Jongsu Kim , Claude LeBrun , Massimiliano Pontecorvo

This article considers the existence and regularity of Kahler-Einstein metrics on a compact Kahler manifold $M$ with edge singularities with cone angle $2\pi\beta$ along a smooth divisor $D$. We prove existence of such metrics with…

Differential Geometry · Mathematics 2015-12-01 T. Jeffres , Rafe Mazzeo , Yanir A. Rubinstein