Results 11 to 20 of about 71 (52)
ON SOME RIEMANNIAN MANIFOLDS ADMITTING TORSE-FORMING VECTOR FIELDS
Demonstratio Mathematica, 1985 The following theorem is proved: If in a Riemannian manifold (M,g) with dim \(M\geq 4\) the covariant derivative \(R_{ij,k}\) of the Ricci tensor is symmetric in all indices, if \(R_{ij}[\ell m]=0\), and if there exists a vector field \(v_ i\) such that \(v_{i,j}=Fg_{ij}+A_ jv_ i\) with a certain scalar field F and a vector field \(A_ j\) (i.e.
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Curves in Riemannian manifolds making prescribed angles with torse-forming vector fields
Journal of Geometry and PhysicsIn this paper, we introduce the notion of a prescribed angle curve in a Riemannian manifold associated with a pair $(\mathcal{V},θ)$, where $\mathcal{V}$ is a unit vector field along the curve and $θ$ denotes the angle between $\mathcal{V}$ and the principal normal vector of the curve. When $\mathcal{V}$ is a torse-forming vector field, we establish an
Muhittin Evren Aydin
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On Kaehlerian torse-forming vector fields [PDF]
Kodai Mathematical Journal, 1979 Seiichi Yamaguchi
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A Characterization of GRW Spacetimes
Mathematics, 2021 We show presence a special torse-forming vector field (a particular form of torse-forming of a vector field) on generalized Robertson–Walker (GRW) spacetime, which is an eigenvector of the de Rham–Laplace operator.
Ibrahim Al-Dayel +2 more
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Mathematics, 2022 Sufficient conditions for a Lorentzian generalized quasi-Einstein manifold M,g,f,μ to be a generalized Robertson–Walker spacetime with Einstein fibers are derived. The Ricci tensor in this case gains the perfect fluid form.
Sameh Shenawy +3 more
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General Relativistic Space-Time with η1-Einstein Metrics
Mathematics, 2022 The present research paper consists of the study of an η1-Einstein soliton in general relativistic space-time with a torse-forming potential vector field.
Yanlin Li +4 more
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Conformal η‐Ricci‐Yamabe Solitons within the Framework of ϵ‐LP‐Sasakian 3‐Manifolds
Advances in Mathematical Physics, Volume 2022, Issue 1, 2022., 2022 In the present note, we study ϵ‐LP‐Sasakian 3‐manifolds M3(ϵ) whose metrics are conformal η‐Ricci‐Yamabe solitons (in short, CERYS), and it is proven that if an M3(ϵ) with a constant scalar curvature admits a CERYS, then £Uζ is orthogonal to ζ if and only if Λ − ϵσ = −2ϵl + (mr/2) + (1/2)(p + (2/3)). Further, we study gradient CERYS in M3(ϵ) and proved
Abdul Haseeb +2 more
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Imperfect Fluid Generalized Robertson Walker Spacetime Admitting Ricci‐Yamabe Metric
Advances in Mathematical Physics, Volume 2021, Issue 1, 2021., 2021 In the present paper, we investigate the nature of Ricci‐Yamabe soliton on an imperfect fluid generalized Robertson‐Walker spacetime with a torse‐forming vector field ξ. Furthermore, if the potential vector field ξ of the Ricci‐Yamabe soliton is of the gradient type, the Laplace‐Poisson equation is derived.
Ali H. Alkhaldi +4 more
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A Note on LP‐Sasakian Manifolds with Almost Quasi‐Yamabe Solitons
Journal of Mathematics, Volume 2021, Issue 1, 2021., 2021 We categorize almost quasi‐Yamabe solitons on LP‐Sasakian manifolds and their CR‐submanifolds whose potential vector field is torse‐forming, admitting a generalized symmetric metric connection of type (α, β). Finally, a nontrivial example is provided to confirm some of our results.
Sunil Kumar Yadav +3 more
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Harmonic Maps and Torse-Forming Vector Fields
International Electronic Journal of Geometry, 2020 In this paper, we prove that any harmonic map from a compact orientable Riemannian manifoldwithout boundary (or from complete Riemannian manifold) (M, g) to Riemannian manifold (N, h)is necessarily constant, with (N, h) admitting a torse-forming vector field satisfying some condition.
Ahmed Mohammed Cherif, Mustapha Djaa
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