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Related papers: Harmonic almost contact structures

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In this paper, a comprehensive study of contact and Sasakian structures on the indicatrix bundle of Finslerian warped product manifolds is reconstructed. In addition, the Kahler structure on the tangent bundle of these manifolds is studied…

Metric Geometry · Mathematics 2021-09-14 Hassan Attarchi , Morteza Mirmohammad Rezaii

We consider 5-manifolds with a contact form arising from a hypo structure, which we call \emph{hypo-contact}. We provide conditions which imply that there exists such a structure on an oriented hypersurface of a 6-manifold with a half-flat…

Differential Geometry · Mathematics 2008-06-20 Luis C. de Andrés , Marisa Fernández , Anna Fino , Luis Ugarte

The theory of harmonic vector fields on Riemannian manifolds is generalised to pseudo-Riemannian manifolds. Harmonic conformal gradient fields on pseudo-Euclidean hyperquadrics are classified up to congruence, as are harmonic Killing fields…

Differential Geometry · Mathematics 2016-10-31 R. M. Friswell , C. M. Wood

We study the conditions under which an almost Hermitian structure $(G,J)$ of general natural lift type on the cotangent bundle $T^*M$ of a Riemannian manifold $(M,g)$ is K\" ahlerian. First, we obtain the algebraic conditions under which…

Differential Geometry · Mathematics 2008-10-09 S. L. Druta

We construct some lift of an almost complex structure to the cotangent bundle, using a connection on the base manifold. This generalizes the complete lift defined by I.Sato and the horizontal lift introduced by K.Yano and S.Ishihara. We…

Complex Variables · Mathematics 2007-05-23 Florian Bertrand

We survey some recent results concerning the behaviour of the contact structure defined on the boundary of a complex isolated hypersurface singularity or on the boundary at infinity of a complex polynomial.

Complex Variables · Mathematics 2017-10-10 C. Caubel , M. Tibar

We define naturally Hermite-Lorentz metrics on almost-complex manifolds as special case of pseudo-Riemannian metrics compatible with the almost complex structure. We study their isometry groups.

Differential Geometry · Mathematics 2017-01-03 Ali Ben-Ahmed , Abdelghani Zeghib

This survey reviews results on harmonic maps into spaces of non-positive curvature, with a focus on targets that lack smooth structure. More precisely, we consider targets that are complete metric spaces with non-positive curvature in the…

Differential Geometry · Mathematics 2025-10-16 Georgios Daskalopoulos , Chikako Mese

We provide a new, self-contained and more conceptual proof of the result that an almost contact metric manifold of dimension greater than 5 is Sasakian if and only if it is nearly Sasakian.

Differential Geometry · Mathematics 2019-09-13 Beniamino Cappelletti-Montano , Antonio De Nicola , Giulia Dileo , Ivan Yudin

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

For each connected complex reductive group G, we find a family of new examples of complex quasi-Hamiltonian G-spaces with G-valued moment maps. These spaces arise naturally as moduli spaces of (suitably framed) meromorphic connections on…

Differential Geometry · Mathematics 2026-03-10 Philip Boalch

In this paper, we initiate the study of lightlike hypersurfaces of an $(\epsilon)$-almost paracontact metric manifold which are tangent to the structure vector field. In particular, we give definitions of invariant lightlike hypersurfaces…

Differential Geometry · Mathematics 2014-12-23 Selcen Yüksel Perktaş , Erol Kılıç , Mukut Mani Tripathi

We discuss asymptotically hyperbolic manifold with a noncompact boundary which is close to a horosphere in a certain sense. The model case is a horoball or the complement of a horoball in standard hyperbolic space. We show some geometric…

Differential Geometry · Mathematics 2021-02-18 Xiaoxiang Chai

This paper addresses the approximation of fractional harmonic maps. Besides a unit-length constraint, one has to tackle the difficulty of nonlocality. We establish weak compactness results for critical points of the fractional Dirichlet…

Numerical Analysis · Mathematics 2021-04-21 Harbir Antil , Sören Bartels , Armin Schikorra

In this paper we define and study pseudoholomorphic vector bundles structures, particular cases of which are tangent and normal bundle almost complex structures. These are intrinsically related to the Gromov D-operator. As an application we…

Complex Variables · Mathematics 2007-05-23 B. Kruglikov

We study compatible contact structures of fibered Seifert multilinks in homology 3-spheres and especially give a necessary and sufficient condition for the contact structure to be tight in the case where the Seifert fibration is positively…

Geometric Topology · Mathematics 2010-11-30 Masaharu Ishikawa

Quasi-Hermitian quantum systems, including $\mathcal{PT}$-symmetric ones, can be mapped to equivalent Hermitian systems via a similarity transformation that redefines the inner product with a positive-definite metric operator. Although an…

Quantum Physics · Physics 2026-05-12 Ming-Zhang Wang , Xu-Yang Hou , Hao Guo

Let $M$ be a three-dimensional contact manifold and $\psi:D\setminus\{0\}\to M\times{\Bbb R}$ a finite-energy pseudoholomorphic map from a punctured disc in ${\Bbb C}$, that is asymptotic to a periodic orbit of the Reeb vector field. This…

Complex Variables · Mathematics 2007-05-23 Adam Harris , Krzysztof Wysocki

In this continuation of \cite{BK} we investigate the non-abelian Hodge correspondence on compact Sasakian manifolds with emphasis on the quasi-regular case. On quasi-regular Sasakian manifolds, we introduce the notions of quasi-regularity…

Differential Geometry · Mathematics 2023-09-22 Indranil Biswas , Hisashi Kasuya

Non-self-adjoint dynamical systems, e.g., nonholonomic systems, can admit an almost Poisson structure, which is formulated by a kind of Poisson bracket satisfying the usual properties except for the Jacobi identity. A general theory of the…

Symplectic Geometry · Mathematics 2008-10-22 Yongxin Guo , Chang Liu , Shixing Liu , Peng Chang
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