Results 81 to 90 of about 431,181 (185)

Super Quasi-Einstein Warped Products Manifolds with Respect to Affine Connections

Axioms
In this paper, we investigate warped products on super quasi-Einstein manifolds under affine connections. We explore their fundamental properties, establish conditions for their existence, and prove that these manifolds can also be nearly quasi-Einstein ...
Mohd Vasiulla, Mohabbat Ali, Meraj Ali Khan, Ibrahim Aldayel   +3 more
doaj   +1 more source

Sphere Theorems for σ_k-Einstein Manifolds

Axioms
A problem that geometers have always been concerned with is when a closed manifold is isometric to a round sphere. A classical result shows that a closed locally conformally flat Einstein manifold is always isometric to a quotient of a round sphere.
Jingyang Zhong, Xinran Mu
doaj   +1 more source

There Are No Conformal Einstein Rescalings of Pseudo-Riemannian Einstein Spaces with n Complete Light-Like Geodesics

Mathematics, 2019
In the present paper, we study conformal mappings between a connected n-dimension pseudo-Riemannian Einstein manifolds. Let g be a pseudo-Riemannian Einstein metric of indefinite signature on a connected n-dimensional manifold M.
Josef Mikeš, Irena Hinterleitner, Nadezda Guseva   +2 more
doaj   +1 more source

Characterizing ϕRic-Vector Fields and Quasi-Einstein Manifolds on Multiply Warped Product Manifolds

International Journal of Mathematics and Mathematical Sciences
We characterize multiply warped product manifolds with ϕRic-vector fields. We give the necessary and sufficient conditions for the lift of a vector field on a factor manifold to be the ϕRic-vector field.
Moctar Traore, Ameth Ndiaye, Mansour Sane   +2 more
doaj   +1 more source

AdS geometry from CFT on a general conformally flat manifold

Nuclear Physics B, 2018
We construct an anti-de-Sitter (AdS) geometry from a conformal field theory (CFT) defined on a general conformally flat manifold via a flow equation associated with the curved manifold, which we refer to as the primary flow equation.
Sinya Aoki, Shuichi Yokoyama
doaj   +1 more source

Einstein structure of four-manifolds

Journal of Geometry and Physics
v3: 27 pages, 1 figure, Sections 4 & 5 added; to appear in Journal of Geometry and ...
Jeongwon Ho, Kyung Kiu Kim, Hyun Seok Yang   +2 more
openaire   +2 more sources

Identifying Constant Curvature Manifolds, Einstein Manifolds, and Ricci Parallel Manifolds [PDF]

The Journal of Geometric Analysis, 2018
We establish variational formulas for Ricci upper and lower bounds, as well as a derivative formula for the Ricci curvature. As applications, constant curvature manifolds, Einstein manifolds and Ricci parallel manifolds are identified, respectively, with different integral-differential formulas and semigroup inequalities.
openaire   +4 more sources

On Calabi's Inhomogeneous Einstein-Kaehler Manifolds [PDF]

Proceedings of the American Mathematical Society, 1977
We use some information on Lie groups to replace a long computation of Calabi, proving that certain complete Einstein-Kaehler manifolds are not locally homogeneous, and finding their isometry groups.
openaire   +2 more sources

Generalized pseudo Ricci symmetric manifolds with semi-symmetric metric connection

Kuwait Journal of Science, 2014
In this paper, firstly an example of a manifold with almost constant curvature and nearly quasi constant curvature which is neither quasi Einstein nor nearly quasi Einstein is given.
SEZGIN ALTAY DEMIRBAG
doaj  

A Kähler Einstein structure on the tangent bundle of a space form

International Journal of Mathematics and Mathematical Sciences, 2001
We obtain a Kähler Einstein structure on the tangent bundle of a Riemannian manifold of constant negative curvature. Moreover, the holomorphic sectional curvature of this Kähler Einstein structure is constant.
Vasile Oproiu
doaj   +1 more source