English
Related papers

Related papers: Almost contact structures on manifolds with a $G_2…

200 papers

We construct and study the supersymmetry properties of the weighted projective spaces $\mathbb{WCP}^2$ and $\mathbb{WCP}^3$. These are topologically $\mathbb{CP}^n$ with $n+1$ orbifold singularities and as such are higher dimensional…

High Energy Physics - Theory · Physics 2025-12-02 Andrea Conti , Niall T. Macpherson

We show that an oriented elliptic 3-manifold admits a universally tight positive contact structure iff the corresponding group of deck transformations on $S^3$ preserves a standard contact structure pointwise. We also relate univerally…

Geometric Topology · Mathematics 2007-05-23 Siddhartha Gadgil

Almost contact manifolds with B-metric are considered. There are studied three natural connections (i.e. linear connections preserving the structure tensors) determined by conditions for their torsions. These connections are investigated on…

Differential Geometry · Mathematics 2015-06-23 Miroslava Ivanova , Hristo Manev

We introduce generalized almost contact structures which admit the $B$-field transformations on odd dimensional manifolds. We provide definition of generalized Sasakain structures from the view point of the generalized almost contact…

Differential Geometry · Mathematics 2012-12-27 Ken'ichi Sekiya

Almost paracontact manifolds of an odd dimension having an almost paracomplex structure on the paracontact distribution are studied. The components of the fundamental (0,3)-tensor, derived by the covariant derivative of the structure…

Differential Geometry · Mathematics 2019-08-07 Mancho Manev , Veselina Tavkova

Hitchin shows that half-flat SU(3)-structures on a 6-dimensional manifold M can be lifted to parallel G_{2}-structure on the product $M\times\mathbb{R}$. We show that Hitchin's approach can also be used to construct nearly parallel…

Differential Geometry · Mathematics 2007-07-16 Sebastian Stock

3-quasi-Sasakian manifolds were recently studied by the authors as a suitable setting unifying 3-Sasakian and 3-cosymplectic geometries. In this paper some geometric properties of this class of almost 3-contact metric manifolds are briefly…

Differential Geometry · Mathematics 2008-08-03 Beniamino Cappelletti Montano , Antonio De Nicola , Giulia Dileo

Almost hypercomplex manifolds with Hermitian and anti-Hermitian metrics are considered. A linear connection $D$ is introduced such that the structure of these manifolds is parallel with respect to D. Of special interest is the class of the…

Differential Geometry · Mathematics 2012-05-08 Mancho Manev

Cosymplectic and normal almost contact structures are analogues of symplectic and complex structures that can be defined on 3-manifolds. Their existence imposes strong topological constraints. Generalized geometry offers a natural common…

Differential Geometry · Mathematics 2026-05-21 Joan Porti , Roberto Rubio

Almost contact manifolds with B-metric are considered. Of special interest are the so-called vertical classes of the almost contact B-metric manifolds. Curvature properties of these manifolds are studied. An example of 5-dimensional…

Differential Geometry · Mathematics 2012-03-27 Mancho Manev

The author is planning if possible classify all three-dimensional $(\kappa,\mu)$-manifolds wether contact metric, almost cosymplectic, para-contact metric, almost para-cosymplectic. Of course classification in contact or almost cosymplectic…

Differential Geometry · Mathematics 2020-06-30 Piotr Dacko

In this paper, the notion of an almost contact K\"ahlerian structure is introduced. The interior geometry of almost contact K\"ahlerian spaces is investigated. On the zero-curvature distribution of an almost contact metric structure, as on…

Differential Geometry · Mathematics 2013-01-15 Sergey V. Galaev

We consider normal almost contact structures on a Riemannian manifold and, through their associated sections of an ad-hoc twistor bundle, study their harmonicity, as sections or as maps. We rewrite these harmonicity equations in terms of…

Differential Geometry · Mathematics 2023-10-18 E. Loubeau , E. Vergara-Diaz

In this paper we construct and study almost paracontact metric structures $(\varphi ,\xi ,\eta ,g)$ on a 3-dimensional Walker manifold $(M,g)$ with respect to a local basis only by the coordinate functions of a unit space-like vector field…

Differential Geometry · Mathematics 2025-09-29 Galia Nakova , Cornelia-Livia Bejan

We study a class of simply connected manifolds in all odd dimensions greater than 3 that exhibit an infinite number of toric contact structures of Reeb type that are inequivalent as contact structures. We compute the cohomology ring of our…

Differential Geometry · Mathematics 2014-04-16 Charles P. Boyer , Christina W. Tønnesen-Friedman

It is provided an overview of existed results concerning classification of contact metric, almost cosymplectic and almost Kenmotsu $(\kappa,\mu)$-manifolds. In the case of dimension three it is described in full details structure of contact…

Differential Geometry · Mathematics 2020-09-23 Piotr Dacko

In this paper, we construct complex metric structures on complex hypersurfaces in hyperkahler manifolds. This construction is that in contact geometry.

Differential Geometry · Mathematics 2015-11-04 Mitsuhiro Imada

In this thesis we study string compactifications on manifolds equipped with a $G$-structure, placing a special emphasis on the interplay between geometry and physics. We follow two complementary approaches. In the first part of the thesis…

High Energy Physics - Theory · Physics 2022-12-29 Mateo Galdeano

We study the sectional curvature of plane distributions on 3-manifolds. We show that if the distribution is a contact structure it is easy to manipulate this curvature. As a corollary we obtain that for every transversally oriented contact…

Differential Geometry · Mathematics 2014-10-01 Vladimir Krouglov

Weak almost contact manifolds, i.e., the linear complex structure on the contact distribution is replaced by a nonsingular skew-symmetric tensor, defined by the author and R. Wolak, allowed us to take a new look at the theory of contact…

Differential Geometry · Mathematics 2024-10-11 Vladimir Rovenski