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Related papers: Weak Almost Contact Structures: a Survey

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We study almost contact metric structures induced by 2-fold vector cross products on manifolds with $G_2$ structures. We get some results on possible classes of almost contact metric structures. Finally we give examples.

Differential Geometry · Mathematics 2016-01-08 Nülifer Özdemir , Mehmet Solgun , Şirin Aktay

This paper is a study of almost contact statistical manifolds. Especially this study is focused on almost cosymplectic statistical manifolds. We obtained basic properties of such manifolds. It is proved a characterization theorem and a…

Differential Geometry · Mathematics 2018-01-31 Aziz Yazla , İrem Küpeli Erken , Cengizhan Murathan

In this article, we study an almost contact metric structure on a $G_2$-manifold constructed by Arikan, Cho and Salur in via the classification of almost contact metric structures given by Chinea and Gonzalez. In particular, we characterize…

Differential Geometry · Mathematics 2015-01-29 Albert J. Todd

We review the construction of almost contact metric (three-) structures, abbreviated ACM(3)S, on manifolds with a $G_2$ structure. These are of interest for certain supersymmetric configurations in string and M-theory. We compute the…

High Energy Physics - Theory · Physics 2021-10-20 Xenia de la Ossa , Magdalena Larfors , Matthew Magill

An almost contact metric structure is parametrized by a section of an associated homogeneous fibre bundle, and conditions for this to be a harmonic section, and a harmonic map, are studied. These involve the characteristic vector field, and…

Differential Geometry · Mathematics 2007-05-23 E. Vergara-Diaz , C. M. Wood

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

Many authors have studied Ricci solitons and their analogs within the framework of (almost) contact geometry. In this article, we thoroughly study the $(m,\rho)$-quasi-Einstein structure on a contact metric manifold. First, we prove that if…

Differential Geometry · Mathematics 2020-10-30 Dhriti Sundar Patra , Vladimir Rovenski

In this paper we generalize the main notions from the geometry of (almost) contact manifolds in the category of Lie algebroids. Also, using the framework of generalized geometry, we obtain an (almost) contact Riemannian Lie algebroid…

Differential Geometry · Mathematics 2016-11-14 Cristian Ida , Paul Popescu

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

In this work, we prove that every complex contact structure gives rise to a distinguished type of almost contact metric 3-structure. As an application of our main result, we provide several new examples of manifolds which admit taut contact…

Differential Geometry · Mathematics 2020-09-24 Eder M. Correa

We consider an almost complex manifold with Norden metric (i. e. a metric with respect to which the almost complex structure is an anti-isometry). On such a manifold we study a linear connection preserving the almost complex structure and…

Differential Geometry · Mathematics 2011-01-24 Dimitar Mekerov

The subject of investigations are the almost hypercomplex manifolds with Hermitian and anti-Hermitian (Norden) metrics. A linear connection D is introduced such that the structure of these manifolds is parallel with respect to D and its…

Differential Geometry · Mathematics 2012-05-08 Mancho Manev , Kostadin Gribachev

In an earlier paper we discussed soldered forms, multivector fields and Riemannian metrics. In particular, we showed that a Riemannian submanifold is totally geodesic iff the metric is soldered to the submanifold. In the present note we…

Differential Geometry · Mathematics 2010-07-01 Izu Vaisman

On a sub-Riemannian manifold, a connection with skew-symmetric torsion is defined as the unique connection from the class of $N$-connections that has this property. Two cases are considered separately: sub-Riemannian structure of even rank,…

Differential Geometry · Mathematics 2021-08-10 Sergey V. Galaev

We introduce the concept of $\varepsilon\,$-contact metric structures on oriented (pseudo-)Riemannian three-manifolds, which encompasses the usual Riemannian contact metric, Lorentzian contact metric and para-contact metric structures, but…

Differential Geometry · Mathematics 2022-10-13 Ángel Murcia

Connections with (skew-symmetric) torsion on non-symmetric Riemannian manifold satisfying the Einstein metricity condition (NGT with torsion) are considered. It is shown that an almost Hermitian manifold is an NGT with torsion if and only…

Differential Geometry · Mathematics 2016-03-23 Stefan Ivanov , Milan Zlatanovic

Is is known that the loop space associated to a Riemannian manifold admits a quasi-symplectic structure. This article shows that this structure is not likely to recover the underlying Riemannian metric by proving a result that is a strong…

Symplectic Geometry · Mathematics 2010-09-16 Vicente Munoz , Francisco Presas

The article contains a survey of our results on weakly commensurable arithmetic and general Zariski-dense subgroups, length-commensurable and isospectral locally symmetric spaces and of related problems in the theory of semi-simple agebraic…

Group Theory · Mathematics 2013-11-25 Gopal Prasad , Andrei S. Rapinchuk

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

In this document we present a twistor correspondence for half-flat almost-Grassmannian structures on real and complex manifolds. We provide foundational results regarding local theory in the complex setting and a global correspondence when…

Differential Geometry · Mathematics 2023-04-18 Matthew Lam