中文
相关论文

相关论文: A Note on Doubly Warped Product Contact CR-Submani…

200 篇论文

In this paper we give a survey of the constructions in math.DG/0510061 of several new invariants for CR and contact manifolds. The latter extend previous constructions of Hirachi and Boutet de Monvel. In addition, we give simple…

微分几何 · 数学 2007-05-23 Raphael Ponge

In this paper, we introduce horizontal and vertical warped product Finsler manifold. We prove that every C-reducible or proper Berwaldian doubly warped product Finsler manifold is Riemannian. Then, we find the relation between Riemmanian…

微分几何 · 数学 2011-11-01 E. Peyghan , A. Tayebi

In this paper, we study a new generalized class of $\mathcal{P}\mathcal{R}$-warped product submanifolds under the name $\mathcal{P}\mathcal{R}$-pseudo-slant warped product submanifolds in para-K\"{a}hler manifolds $\bar{M}$. The results of…

微分几何 · 数学 2024-08-09 A. Sharma , S. K. Srivastava

In the breakthrough paper [V. Mu\~noz, A Smale-Barden manifold admitting K-contact but not Sasakian structure, 2024, 10.4171/JEMS/1496], it is constructed the first example of a simply connected compact 5-manifold (aka.\ Smale-Barden…

辛几何 · 数学 2025-03-18 Vicente Muñoz , Juan Rojo

We study the Lie algebra of infinitesimal isometries on compact Sasakian and K--contact manifolds. On a Sasakian manifold which is not a space form or 3--Sasakian, every Killing vector field is an infinitesimal automorphism of the Sasakian…

微分几何 · 数学 2019-01-08 Florin Belgun , Andrei Moroianu , Uwe Semmelmann

We consider a compact pseudo-hermitian manifold (M,\theta, J), that is a manifold equipped with a contact form \theta and CR structure J. We consider a conformal deformation of the contact form to obtain a complete, singular contact form…

微分几何 · 数学 2025-04-10 Sagun Chanillo , Paul C. Yang

Sasakian manifolds are odd-dimensional counterpart to Kahler manifolds. They can be defined as contact manifolds equipped with an invariant Kahler structure on their symplectic cone. The quotient of this cone by the homothety action is a…

微分几何 · 数学 2024-05-24 Liviu Ornea , Misha Verbitsky

We solve the problem posed by Boyer and Galicki about the existence of K-contact simply connected manifolds with no Sasakian structure. Although the result lies in the framework of metric contact geometry, our methods come from contact and…

微分几何 · 数学 2015-05-19 Boguslaw Hajduk , Aleksy Tralle

Let $M=X\times Y$ be the product of two complex manifolds of positive dimensions. In this paper, we prove that there is no complete K\"ahler metric $g$ on $M$ such that: either (i) the holomorphic bisectional curvature of $g$ is bounded by…

微分几何 · 数学 2009-09-30 Luen-Fai Tam , Chengjie Yu

We introduce the concept of a base conformal warped product of two pseudo-Riemannian manifolds. We also define a subclass of this structure called as a special base conformal warped product. After, we explicitly mention many of the relevant…

微分几何 · 数学 2008-08-25 Fernando Dobarro , Bulent Unal

It is introduced a differentiable manifold with almost contact 3-structure which consists of an almost contact metric structure and two almost contact B-metric structures. The product of this manifold and a real line is an almost…

微分几何 · 数学 2017-11-21 Mancho Manev

The object of the present paper is to obtain the characterization of a warped product semi-Riemannian manifold with a special type of recurrent like structure, called super generalized recurrent. As consequence of this result we also find…

微分几何 · 数学 2015-04-14 Absos Ali Shaikh , Haradhan Kundu , Md. Showkat Ali

In monograph of D. E. Blair "Riemannian geometry of contact and symplectic manifolds" and in the paper of S. Zamkovoy "Canonical connections on paracontact manifolds", the curvature identities respectively for contact and paracontact metric…

微分几何 · 数学 2012-09-24 Joanna Wełyczko

We propose a machine learning approach to study topological quantities related to the Sasakian and $G_2$-geometries of contact Calabi-Yau $7$-manifolds. Specifically, we compute datasets for certain Sasakian Hodge numbers and for the…

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…

微分几何 · 数学 2014-04-16 Charles P. Boyer , Christina W. Tønnesen-Friedman

We study some sub-Riemannian objects (such as horizontal connectivity, horizontal connection, horizontal tangent plane, horizontal mean curvature) in hypersurfaces of sub-Riemannian manifolds. We prove that if a connected hypersurface in a…

微分几何 · 数学 2007-05-23 Kang-Hai Tan , Xiao-Ping Yang

We prove global estimates for the sub-Riemannian distance of CR Sasakian manifolds with non negative horizontal Webster-Tanaka Ricci curvature. In particular, in this setting, large sub-Riemannian balls are comparable to Riemannian balls.

微分几何 · 数学 2011-10-07 Fabrice Baudoin , Michel Bonnefont

Koll\'ar has found subtle obstructions to the existence of Sasakian structures on 5-dimensional manifolds. In the present article we develop methods of using these obstructions to distinguish K-contact manifolds from Sasakian ones. In…

辛几何 · 数学 2020-03-06 Vicente Muñoz , Juan Angel Rojo , Aleksy Tralle

In this paper biharmonic maps between doubly warped product manifolds are studied. We show that the inclusion maps of Riemannian manifolds $B$ and $F$ into the doubly warped product $_{f}B\times_{b}F$ can not be proper biharmonic maps. Also…

微分几何 · 数学 2008-08-01 Selcen Yüksel Perktaş , Erol Kılıç

We study 5-dimensional Riemannian manifolds that admit an almost contact metric structure. In particular, we generalize the class of quasi-Sasaki manifolds and characterize these structures by their intrinsic torsion. Among other things, we…

微分几何 · 数学 2012-11-14 Christof Puhle