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Related papers: On the uniqueness of almost-Kaehler structures

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We give an elementary proof of the fact that any 4-dimensional para-Hermitian manifold admits a unique para-Kaehler--Weyl structure. We then use analytic continuation to pass from the para-complex to the complex setting and thereby show any…

Differential Geometry · Mathematics 2012-10-26 Peter Gilkey , Stana Nikcevic

In the paper we consider pseudo bihermitian structures - a pair of complex structures compatible with a pseudo Riemannian metric. As in the positive definite case we establish its relations with generalized (pseudo) Kaehler geometry and…

Differential Geometry · Mathematics 2011-04-22 J. Davidov , G. Grantcharov , O. Muskarov , M. Yotov

It is an open problem to provide a characterization of quasiconformally homogeneous Riemann surfaces. We show that given the current literature, this problem can be broken into four open cases with respect to the topology of the underlying…

Geometric Topology · Mathematics 2024-03-11 Ara Basmajian , Nicholas G. Vlamis

We study invariant pseudo-K\"ahler structures on a solvmanifold $G$ such that the Lie algebra $\mathfrak{g}$ is almost abelian, that is $\mathfrak{g}=\mathfrak{h}\rtimes\mathbb{R}$, with $\mathfrak{h}$ abelian; comparing with the…

Differential Geometry · Mathematics 2025-06-30 Diego Conti , Alejandro Gil-García

In this short note, we prove that on a compact K\"ahler variety $X$ with log terminal singularities and $c_1(X)=0$, any singular Ricci-flat K\"ahler metric has orbifold singularities in restriction to the orbifold locus of $X$.

Differential Geometry · Mathematics 2025-09-12 Henri Guenancia , Chung-Ming Pan , Mihai Păun

The total space of the tangent bundle of a K\"ahler manifold admits a canonical K\"ahler structure. Parallel translation identifies the space ${\Bbb{T}}$ of oriented affine lines in ${\Bbb{R}}^3$ with the tangent bundle of $S^2$. Thus, the…

Differential Geometry · Mathematics 2021-11-15 Brendan Guilfoyle , Wilhelm Klingenberg

In this paper, we study the properties of coverings of locally conformally K\"ahler (LCK) spaces with singularities. We begin by proving that a space is LCK if any only if its universal cover is K\"ahler, thereby generalizing a result from…

Differential Geometry · Mathematics 2020-01-22 Ovidiu Preda , Miron Stanciu

We introduce a "qualitative property" for Bott-Chern cohomology of complex non-K\"ahler manifolds, which is motivated in view of the study of the algebraic structure of Bott-Chern cohomology. We prove that such a property characterizes the…

Complex Variables · Mathematics 2019-12-23 Daniele Angella , Nicoletta Tardini

Let L\subset V=\bR^{k,l} be a maximally isotropic subspace. It is shown that any simply connected Lie group with a bi-invariant flat pseudo-Riemannian metric of signature (k,l) is 2-step nilpotent and is defined by an element \eta \in…

Differential Geometry · Mathematics 2009-08-03 Vicente Cortés , Lars Schäfer

In this article we apply a Bochner type formula to show that on a compact conformally flat riemannian manifold (or half-conformally flat in dimension 4) certain types of orthogonal almost-complex structures, if they exist, give the absolute…

Differential Geometry · Mathematics 2007-05-23 G. Bor , L. Hernández-Lamoneda , M. Salvai

In this expository article, we illustrate how two independent flat structures on minimal surfaces induce a harmonic function, which captures the uniqueness of Enneper's surface.

Differential Geometry · Mathematics 2018-02-23 Hojoo Lee

A $p$-K\"ahler structure on a complex manifold of complex dimension $n$ is given by a $d$-closed transverse real $(p,p)$-form. In the paper we study the existence of $p$-K\"ahler structures on compact quotients of simply connected Lie…

Differential Geometry · Mathematics 2024-04-04 Anna Fino , Asia Mainenti

We prove the formality and the evenness of odd-degree Betti numbers for compact K\"ahler orbifolds, by adapting the classical proofs for K\"ahler manifolds. As a consequence, we obtain examples of symplectic orbifolds not admitting any…

Differential Geometry · Mathematics 2016-12-30 Giovanni Bazzoni , Indranil Biswas , Marisa Fernández , Vicente Muñoz , Aleksy Tralle

We show that every quaternion-K\"ahler manifold of negative scalar curvature is stable as an Einstein manifold and therefore scalar curvature rigid. In particular, this implies that every irreducible nonpositive Einstein manifold of special…

Differential Geometry · Mathematics 2024-12-19 Klaus Kroencke , Uwe Semmelmann

There is a rich theory of so-called (strict) nearly Kaehler manifolds, almost-Hermitian manifolds generalising the famous almost complex structure on the 6-sphere induced by octonionic multiplication. Nearly Kaehler 6-manifolds play a…

Differential Geometry · Mathematics 2018-05-09 Lorenzo Foscolo , Mark Haskins

In this paper we develop in detail the geometric constructions that lead to many uniqueness results for the determination of polyhedral sets, typically scatterers, by a finite minimal number of measurements. We highlight how unique…

Analysis of PDEs · Mathematics 2023-10-10 Luca Rondi

We prove that the compact Kaehler manifolds with first Chern class nonnegative that admit holomorphic parabolic geometries are the flat bundles of rational homogeneous varieties over complex tori. We also prove that the compact Kaehler…

Differential Geometry · Mathematics 2019-11-12 Benjamin McKay

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

We obtain necessary conditions for the existence of special K\"ahler structures with isolated singularities on compact Riemann surfaces. We prove that these conditions are also sufficient in the case of the Riemann sphere and, moreover, we…

Differential Geometry · Mathematics 2020-03-11 Andriy Haydys , Bin Xu

In this article, we consider the almost Hermitian structure on $TM$ induced by a pair of a metric and an affine connection on $M$. We find the conditions under which $TM$ admits almost K\"ahler structures, K\"ahler structures and Einstein…

Differential Geometry · Mathematics 2025-03-24 Hiroyasu Satoh
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