Results 1 to 10 of about 1,987 (109)
Certain Conditions for a Finsler Manifold to Be Isometric with a Finsler Sphere
Analysis and Geometry in Metric Spaces, 2022 We show that if there is a smooth function f on a Finsler n-space M satisfying Δ2f = −kfgΔf for a positive constant k, then M is diffeomorphic with the n-sphere 𝕊n, where g denotes the weighted Riemannian metric.
Yin Songting, Wang Huarong
exaly +2 more sources
Results in Physics, 2021 Static spaces (with perfect fluids) appeared in a natural way both in physics (cf. Hawking and Ellis, 1975) and mathematics (cf. A. Fischer and J. Marsden, Duke Math. J. 42 (3) (1975), 519–547).
Ibrahim Al-Dayel +2 more
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Metric characterizations of some subsets of the real line
Математичні Студії, 2023 A metric space $(X,\mathsf{d})$ is called a {\em subline} if every 3-element subset $T$ of $X$ can be written as $T=\{x,y,z\}$ for some points $x,y,z$ such that $\mathsf{d}(x,z)=\mathsf{d}(x,y)+\mathsf{d}(y,z)$.
I. Banakh +3 more
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Geodesic Vector Fields on a Riemannian Manifold
Mathematics, 2020 A unit geodesic vector field on a Riemannian manifold is a vector field whose integral curves are geodesics, or in other worlds have zero acceleration. A geodesic vector field on a Riemannian manifold is a smooth vector field with acceleration of each of
Sharief Deshmukh +2 more
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Soliton-Type Equations on a Riemannian Manifold
Mathematics, 2022 We study some particular cases of soliton-type equations on a Riemannian manifold. We give an estimation of the first nonzero eigenvalue of the Laplace operator and provide necessary and sufficient conditions for the manifold to be isometric to a sphere.
Nasser Bin Turki +2 more
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A Remarkable Property of Concircular Vector Fields on a Riemannian Manifold
Mathematics, 2020 In this paper, we show that, given a non-trivial concircular vector field u on a Riemannian manifold ( M , g ) with potential function f, there exists a unique smooth function ρ on M that connects u to the gradient of potential function
Ibrahim Al-Dayel +2 more
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Hypersurfaces of a Sasakian manifold - revisited
Journal of Inequalities and Applications, 2021 We study orientable hypersurfaces in a Sasakian manifold. The structure vector field ξ of a Sasakian manifold determines a vector field v on a hypersurface that is the component of the Reeb vector field ξ tangential to the hypersurface, and it also gives
Sharief Deshmukh +3 more
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Characterization of Lagrangian Submanifolds by Geometric Inequalities in Complex Space Forms
Advances in Mathematical Physics, 2021 In this paper, we give an estimate of the first eigenvalue of the Laplace operator on a Lagrangian submanifold Mn minimally immersed in a complex space form.
Lamia Saeed Alqahtani
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Toeplitz Operators with Lagrangian Invariant Symbols Acting on the Poly-Fock Space of ℂn
Journal of Function Spaces, 2021 We introduce the so-called extended Lagrangian symbols, and we prove that the C∗-algebra generated by Toeplitz operators with these kind of symbols acting on the homogeneously poly-Fock space of the complex space ℂn is isomorphic and isometric to the C ...
Jorge Luis Arroyo Neri +3 more
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Hypersurfaces of a Sasakian Manifold
Mathematics, 2020 We extend the study of orientable hypersurfaces in a Sasakian manifold initiated by Watanabe. The Reeb vector field ξ of the Sasakian manifold induces a vector field ξ T on the hypersurface, namely the tangential component of ξ to ...
Haila Alodan +3 more
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