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Related papers: Complex nilmanifolds and K\"ahler-like connections

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In this article, we investigate the class of Hermitian manifolds whose Bismut connection has parallel torsion ({\rm BTP} for brevity). In particular, we focus on the case where the manifold is (locally) homogeneous with respect to a group…

Differential Geometry · Mathematics 2026-03-17 Fabio Podestà , Fangyang Zheng

A Hermitian structure on a manifold is called locally conformally K\"ahler (LCK) if it locally admits a conformal change which is K\"ahler. In this survey we review recent results of invariant LCK structures on solvmanifolds and present…

Differential Geometry · Mathematics 2020-04-06 Adrián Andrada , Marcos Origlia

We prove two results on geometric consequences of the representation of restricted holonomy group of a Hermitian connection. The first result concerns when such a Hermitian manifold is K\"ahler in terms of the torsion and the irreducibility…

Differential Geometry · Mathematics 2024-10-10 Lei Ni

We establish necessary and sufficient conditions for existence of isometric immersions of a simply connected Riemannian manifold into a two-step nilpotent Lie group. This comprises the case of immersions into $H$-type groups.

Differential Geometry · Mathematics 2008-10-21 J. H. de Lira , M. Melo

We study left-invariant generalized K\"ahler structures on almost abelian Lie groups, i.e., on solvable Lie groups with a codimension-one abelian normal subgroup. In particular, we classify six-dimensional almost abelian Lie groups which…

Differential Geometry · Mathematics 2021-02-09 Anna Fino , Fabio Paradiso

We show that Hermitian metrics with vanishing holomorphic curvature on compact complex manifolds with pseudoeffective canonical bundle are conformally balanced. Pluriclosed metrics with vanishing holomorphic curvature on compact K\"ahler…

Differential Geometry · Mathematics 2024-08-06 Kyle Broder , Kai Tang

We study almost K\"ahler manifolds whose curvature tensor satisfies the second curvature condition of Gray (shortly ${\cal{AK}}_2$). This condition is interpreted in terms of the first canonical Hermitian connection. It turns out that this…

Differential Geometry · Mathematics 2007-05-23 Paul-Andi Nagy

In a Riemannian manifold, the existence of a new connection is proved. In particular cases, this connection reduces to several symmetric, semi-symmetric and quarter-symmetric connections; even some of them are not introduced so far. We also…

Differential Geometry · Mathematics 2008-02-06 Mukut Mani Tripathi

We study almost Hermitian structures admitting a Hermitian connexion with totally skew-symmetric torsion or equivalently, those almost Hermitian structures with totally skew-symmetric Nijenhuis tensor. We investigate up to what extent the…

Differential Geometry · Mathematics 2007-09-11 Paul-Andi Nagy

We investigate L-sectional curvature of S-manifolds with respect to the Rieman- nian connection and to certain semi-symmetric metric and non-metric connections naturally related with the structure, obtaining conditions for them to be…

Differential Geometry · Mathematics 2013-04-23 Mehmet Akif Akyol , Luis M. FernÁndez , Alicia Prieto-MartÍn

We study left-invariant locally conformally K\"ahler structures on Lie groups, or equivalently, on Lie algebras. We give some properties of these structures in general, and then we consider the special cases when its complex structure is…

Differential Geometry · Mathematics 2020-04-06 Adrián Andrada , Marcos Origlia

In this paper, we study the relation between the existence of a negatively (holomorphically) pinched K\"ahler metric on a complex manifold $M$ and its disc bundle contained in a Hermitian line bundle over $M$.

Complex Variables · Mathematics 2025-09-05 Yihong Hao , Mingming Chen , An Wang

We consider nilmanifolds with left-invariant complex structure and prove that small deformations of such structures are again left invariant if the Dolbeault-cohomology of the nilmanifold can be calculated using left-invariant forms. By a…

Algebraic Geometry · Mathematics 2009-10-31 Sönke Rollenske

Let (N,J) be a real 2n-dimensional nilpotent Lie group endowed with an invariant complex structure. A left-invariant Riemannian metric on N compatible with J is said to be minimal, if it minimizes the norm of the invariant part of the Ricci…

Differential Geometry · Mathematics 2013-09-24 Edwin Alejandro Rodriguez Valencia

We investigate a new property for compact Kahler manifolds. Let X be a Kahler manifold of dimension n and let H^{1,1} denote the (1,1) part of its real second cohomology. On this space, we have an degree n form given by cup product. Let K…

Algebraic Geometry · Mathematics 2007-05-23 P. M. H. Wilson

There are studied Lie groups considered as almost hypercomplex Hermitian-Norden manifolds, which are integrable and have the lowest dimension four. It is established a correspondence of the derived Lie algebras of types of invariant…

Differential Geometry · Mathematics 2019-03-22 Hristo Manev

We classify hom-Lie structures with nilpotent twisting map on $3$-dimensional complex Lie algebras, up to isomorphism, and classify all degenerations in such family. The ideas and techniques presented here can be easily extrapolated to…

Rings and Algebras · Mathematics 2019-11-06 Edison Alberto Fernández-Culma , Nadina Elizabeth Rojas

On $4$-symmetric symplectic spaces, invariant almost complex structures -- up to sign -- arise in pairs. We exhibit some $4$-symmetric symplectic spaces, with a pair of "natural" compatible (usually not positive) invariant almost complex…

Differential Geometry · Mathematics 2022-06-14 Michel Cahen , Simone Gutt , Manar Hayyani , Mohammed Raouyane

On a Riemannian almost product manifold $(M,P,g)$ we consider a linear connection preserving the almost product structure $P$ and the Riemannian metric $g$ and having a totally skew-symmetric torsion. We determine the class of the manifolds…

Differential Geometry · Mathematics 2012-05-08 Dimitar Mekerov , Mancho Manev

We introduce a class of hermitian metrics with {\em Lee potential}, that generalize the notion of l.c.K. metrics with potential introduced in \cite{ov} and show that in the classical examples of Calabi and Eckmann of complex structures on…

Differential Geometry · Mathematics 2012-08-22 Florin Belgun