English
Related papers

Related papers: On homogeneous Hermite-Lorentz spaces

200 papers

We discuss a technique to construct Ricci-flat hermitian metrics on complements of (some) anticanonical divisors of almost homogeneous manifolds and discuss when this metric is complete and K\"ahler. This construction has a strong interplay…

Differential Geometry · Mathematics 2007-05-23 Bert Koehler , Marco Kuehnel

We give a partial account of some problems concerning cohomological invariants and metric properties of complex non-K\"ahler manifolds.

Differential Geometry · Mathematics 2026-02-04 Daniele Angella , Nicoletta Tardini

We study Riemannian manifolds carrying a metric connection with parallel, skew-symmetric and closed torsion, which we call in short PSCT manifolds. We prove that PSCT manifolds always locally split into a product of well-understood factors,…

Differential Geometry · Mathematics 2026-05-14 Andrei Moroianu , Paul Schwahn

We proved the existence of supersymmetric Hermitian metrics with torsion on a class of non-Kaehler manifolds.

High Energy Physics - Theory · Physics 2007-05-23 Ji-Xiang Fu , Shing-Tung Yau

We consider a pair of smooth manifolds, which are the counterparts in the even-dimensional and odd-dimensional cases. They are separately an almost complex manifold with Norden metric and an almost contact manifolds with B-metric,…

Differential Geometry · Mathematics 2015-05-06 Mancho Manev

Motivated by the work of Cappell, Deturck, Gluch and Miller, we extend the notion of cohomology of harmonic forms (of a compact manifold with boundary) to the abstract setting of Hilbert complexes. Then, we present some geometric…

Differential Geometry · Mathematics 2025-12-17 Francesco Bei , Mauro Spreafico

We investigate several classes of submanifolds of almost quaternionic skew-Hermitian manifolds $(M^{4n}, Q, \omega)$, including almost symplectic, almost complex, almost pseudo-Hermitian and almost quaternionic submanifolds. In the…

Differential Geometry · Mathematics 2026-01-07 Ioannis Chrysikos , Jan Gregorovič

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

On a smooth connected manifold, we consider all possible locally elliptic and locally bounded measurable coefficient Riemannian metrics called rough Riemannian metrics. We equip this set with an extended metric which is connected if and…

Differential Geometry · Mathematics 2025-07-15 Lashi Bandara , Anisa Hassan

This article investigates the holonomy groups of K-contact sub-pseudo-Riemannian manifolds. The primary result is a proof that the horizontal holonomy group either coincides with the adapted holonomy group or acts as its normal subgroup of…

Differential Geometry · Mathematics 2026-01-16 E. A. Kokin

We study isometries in the contact sub-pseudo-Riemannian geometry. In particular we give an upper bound on the dimension of the isometry group of a general sub-pseudo-Riemannian manifold and prove that the maximal dimension is attained for…

Differential Geometry · Mathematics 2015-12-09 Marek Grochowski , Wojciech Krynski

The aim of this article is to study the Riemann soliton and gradient almost Riemann soliton on certain class of almost Kenmotsu manifolds. Also some suitable examples of Kenmotsu and $(\kappa,\mu)'$-almost Kenmotsu manifolds are constructed…

Differential Geometry · Mathematics 2020-07-15 V. Venkatesha , H. Aruna Kumara , Devaraja Mallesha Naik

This is a survey of old and new results on the problem when a compatible almost complex structure on a Riemannian manifold is a harmonic section or a harmonic map from the manifold into its twistor space. In this context, a special…

Differential Geometry · Mathematics 2016-11-18 Johann Davidov

Almost contact complex Riemannian manifolds, known also as almost contact B-metric manifolds, are in principle equipped with a pair of mutually associated pseudo-Riemannian metrics. Each of these metrics is specialized here as a Yamabe…

Differential Geometry · Mathematics 2023-09-06 Mancho Manev

Let $M=G/H$ be a compact, simply connected, Riemannian homogeneous space, where $G$ is (almost) effective and $H$ is a simple Lie group. In this paper, we first classify all $G$-naturally reductive metrics on $M$, and then all $G$-geodesic…

Differential Geometry · Mathematics 2023-11-28 Z. Chen , Y. Nikolayevsky , Yu. Nikonorov

We study the space of pseudo-holomorphic spheres in compact symplectic manifolds with convex boundary. We show that the theory of Gromov-Witten invariants can be extended to the class of semi-positive manifolds with convex boundary. This…

Symplectic Geometry · Mathematics 2013-02-06 Sergei Lanzat

In this paper, we introduce the notion of a quasi-biharmonic submanifold in a pseudo-Riemannian manifold and classify quasi-biharmonic marginally trapped Lagrangian surfaces in Lorentzian complex space forms.

Differential Geometry · Mathematics 2014-12-03 Toru Sasahara

We study the geometry of compact Lorentzian manifolds that admit a somewhere timelike Killing vector field, and whose isometry group has infinitely many connected components. Up to a finite cover, such manifolds are products (or amalgamated…

Differential Geometry · Mathematics 2010-02-04 Paolo Piccione , Abdelghani Zeghib

A Lie group as a 4-dimensional pseudo-Riemannian manifold is considered. This manifold is equipped with an almost product structure and a Killing metric in two ways. In the first case Riemannian almost product manifold with nonintegrable…

Differential Geometry · Mathematics 2009-07-14 Dimitar Mekerov

We study the six-dimensional pseudo-Riemannian spaces with two time-like coordinates that admit non-homothetic infinitesimal projective transformations. The metrics are manifestly obtained and the projective group properties are determined.…

Differential Geometry · Mathematics 2015-06-26 Zolfira Zakirova