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

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We study some basic properties and examples of Hermitian metrics on complex manifolds whose traces of the curvature of the Chern connection are proportional to the metric itself.

Differential Geometry · Mathematics 2020-07-22 Daniele Angella , Simone Calamai , Cristiano Spotti

We consider and resolve the gap problem for almost quaternion-Hermitian structures, i.e. we determine the maximal and submaximal symmetry dimensions, both for Lie algebras and Lie groups, in the class of almost quaternion-Hermitian…

Differential Geometry · Mathematics 2020-08-19 Boris Kruglikov , Henrik Winther

We consider strict and complete nearly Kaehler manifolds with the canonical Hermitian connection. The holonomy representation of the canonical Hermitian connection is studied. We show that a strict and complete nearly Kaehler is locally a…

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

The aim of this paper is to study self-similar solutions to the symplectic cuvature flow on 6-dimensional nilmanifolds. For this purpose, we focus our attention in the family of symplectic Two- and Three-step nilpotent Lie algebras…

Differential Geometry · Mathematics 2015-03-13 Edison Alberto Fernández-Culma

We give four constructions of non-$\partial\bar\partial$ (hence non-K\"ahler) manifolds: (1) A simply connected page-$1$-$\partial\bar\partial$-manifold (2) A simply connected $dd^c+3$-manifold (3) For any $r\geq 2$, a simply connected…

Algebraic Geometry · Mathematics 2023-06-27 Hisashi Kasuya , Jonas Stelzig

We give a complete classification of left invariant para-K\"ahler structures on four-dimensional simply connected Lie groups up to an automorphism. As an application we discuss some curvatures properties of the canonical connection…

Symplectic Geometry · Mathematics 2021-04-20 Wadia Mansouri , Ahmad Oufkou

There are studied in details 5-dimensional pseudo-Riemannian manifolds equipped with the structure analogous to the almost cosymplectic (almost coKaehler) structure. The curvature by assumption commutes with the structure affinor and all…

Differential Geometry · Mathematics 2013-08-30 Piotr Dacko

A 3-dimensional Riemannian manifold equipped with a tensor structure of type $(1,1)$, whose fourth power is the identity, is considered. This structure acts as an isometry with respect to the metric. A Riemannian almost product manifold…

Differential Geometry · Mathematics 2025-06-06 Iva Dokuzova

In 1976, Milnor classified all Lie groups admitting a flat left-invariant metric. They form a special type of unimodular 2-step solvable groups. Considering Lie groups with Hermitian structure, namely, a left-invariant complex structure and…

Differential Geometry · Mathematics 2026-03-17 Dongmei Zhang , Fangyang Zheng

We consider a closed odd-dimensional oriented manifold $M$ together with an acyclic flat hermitean vector bundle $\cF$. We form the trivial fibre bundle with fibre $M$ over the manifold of all Riemannian metrics on $M$. It has a natural…

dg-ga · Mathematics 2007-05-23 U. Bunke

Lie groups considered as three-dimensional almost paracontact almost paracomplex Riemannian manifolds are investigated. In each basic class of the classification used for the manifolds under consideration, a correspondence is established…

Differential Geometry · Mathematics 2021-06-22 Mancho Manev , Veselina Tavkova

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

For a compact relative K\"ahler fibration over a compact K\"ahler manifold with negative holomorphic sectional curvature, if the relative K\"ahler form on each fiber also exhibits negative holomorphic sectional curvature, we can construct…

Differential Geometry · Mathematics 2026-01-16 Xueyuan Wan

The aim of this note is the study of Einstein condition for para-holomorphic Riemannian metrics in the para-complex geometry framework. Firstly, we make some general considerations about para-complex Riemannian manifolds (not necessarily…

Differential Geometry · Mathematics 2016-10-12 Cristian Ida , Alexandru Ionescu , Adelina Manea

In this article studies questions about the existence of left-invariant K\"{a}hler and semi-para-K\"{a}hler structures on six-dimensional unsolvable Lie groups whose Lie algebras are semidirect products. According to the classification…

Differential Geometry · Mathematics 2024-10-29 N. K. Smolentsev , A. Yu Sokolova

We study the behavior of connections and curvature under the HK/QK correspondence, proving simple formulae expressing the Levi-Civita connection and Riemann curvature tensor on the quaternionic K\"ahler side in terms of the initial…

Differential Geometry · Mathematics 2021-04-01 V. Cortés , A. Saha , D. Thung

We study the interplay between geometrically-Bott-Chern-formal metrics and SKT metrics. We prove that a $6$-dimensional nilmanifold endowed with a invariant complex structure admits an SKT metric if and only if it is…

Differential Geometry · Mathematics 2024-02-12 Tommaso Sferruzza , Adriano Tomassini

A Riemannian metric on a manifold M induces a family of Riemannian metrics on the loop space LM depending on a Sobolev space parameter s. We compute the connection forms of these metrics and the higher symbols of their curvature forms,…

Differential Geometry · Mathematics 2014-05-19 Yoshiaki Maeda , Steven Rosenberg , Fabián Torres-Ardila

Recent work on the relation between a special class of K\"ahler manifolds with positive first Chern class and critical N$=$2 string vacua with c$=$9 is reviewed and extended. (Based on a talk presented at the International Workshop on…

High Energy Physics - Theory · Physics 2008-02-03 R. Schimmrigk

In 1992, Agache and Chaple introduced the concept of a semi-symmetric non-metric connection([1]). The semi-symmetric non-metric connection does not satisfy the Schur`s theorem. The purpose of the present paper is to study some properties of…

Mathematical Physics · Physics 2012-12-20 Ho Tal Yun