Results 11 to 20 of about 207 (126)
Noninvariant Hypersurfaces of a Nearly Trans-Sasakian Manifolds
Journal of Mathematics, 2014 The present paper focuses on the study of noninvariant hypersurfaces of a nearly trans-Sasakian manifold equipped with (f,g,u,v,λ)-structure. Initially some properties of this structure have been discussed.
Satya Prakash Yadav, Shyam Kishor
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A note on η-quasi-umbilical hypersurfaces in almost Hermitian manifolds
Дифференциальная геометрия многообразий фигур, 2023 In the present note, we consider the introduced by Lidia Vasil’evna Stepanova notion of an -quasi-umbilical hypersurface in an almost Hermitian manifold.
M. B. Banaru
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Concurrent Vector Fields on Lightlike Hypersurfaces
Mathematics, 2020 Concurrent vector fields lying on lightlike hypersurfaces of a Lorentzian manifold are investigated. Obtained results dealing with concurrent vector fields are discussed for totally umbilical lightlike hypersurfaces and totally geodesic lightlike ...
Erol Kılıç +2 more
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Mathematische Nachrichten, 2023 18 pages, published in Mathematische ...
D'haene, Marie +2 more
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REMARKS ON MANIFOLDS ADMITTING TOTALLY UMBILICAL HYPERSURFACES
Demonstratio Mathematica, 1978 Zbigniew Olszak
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Impact of Ambient Conformal Vector Fields on Yamabe Solitons on Riemannian Hypersurfaces
MathematicsWe investigate Yamabe solitons on Riemannian hypersurfaces induced by conformal vector fields in Riemannian and Lorentzian manifolds, with an emphasis on the tangential component.
Norah Alshehri
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AxiomsIn this paper, we examine torse-forming vector fields to characterize extrinsic spheres (that is, totally umbilical hypersurfaces with nonzero constant mean curvatures) in Riemannian and Lorentzian manifolds.
Norah Alshehri, Mohammed Guediri
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Characterization of totally umbilical hypersurfaces [PDF]
Proceedings of the American Mathematical Society, 1981 This paper gives a sufficient condition for a complete hypersurface of a Riemannian manifold of constant curvature to be umbilical. The condition will be given by an inequality which is established between the length of the second fundamental tensor and the mean curvature. K. Nomizu and B.
Hasanis, T.
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Totally umbilical hypersurfaces of a locally product Riemannian manifold
Kodai Mathematical Journal, 1967 It is well known that a totally umbilical hypersurface withnon-vanishing mean curvature of a Euclidean space is isometric with a sphere. Toprove this theorem we use, among others, the fact that in a Euclidean space themean curvature of a totally umbilical hypersurface is a constant.In more general Riemannian manifolds, however, there does not exist the
Masafumi Okumura
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Spacelike Hypersurfaces in de Sitter Space
AxiomsA closed conformal vector field in de Sitter space S1n+1c¯ induces a vector field on a spacelike hypersurface M of S1n+1c¯, referred to as the induced vector field on M. This article investigates the characterization of compact spacelike hypersurfaces in
Yanlin Li +3 more
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