Results 31 to 40 of about 179 (133)
ON $\mathcal{T}$-HYPERSURFACES OF A PARASASAKIAN MANIFOLD
, 2021 The main purpose of this paper is to study transversal hypersurface (briefly, $\mathcal{T}$-hypersurface) $P$ of a paraSasakian manifold $M$. We derive results allied with totally geodesic and totally umbilical $\mathcal{T}$-hypersurface of $M$.
Srivastava, Sachin Kumar +2 more
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Totally umbilical hypersurfaces of Spinc manifolds carrying special spinor fields [PDF]
International Journal of Mathematics, 2020 Under some dimension restrictions, we prove that totally umbilical hypersurfaces of Spin[Formula: see text] manifolds carrying a parallel, real or imaginary Killing spinor are of constant mean curvature. This extends to the Spin[Formula: see text] case the result of Kowalski stating that, every totally umbilical hypersurface of an Einstein manifold of
Große, Nadine, Nakad, Roger
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A compact minimal shadow boundary in Euclidean space is totally geodesic [PDF]
, 2011 We prove that a compact minimal shadow boundary of a hypersurface in Euclidean space is totally geodesic. We show that shadow boundaries detect principal directions and umbilical points of a hypersurface.
Antonio J. Di Scala +7 more
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Characterization of totally umbilic hypersurfaces in a space form by circles [PDF]
Czechoslovak Mathematical Journal, 2005 In this paper we characterize totally umbilic hypersurfaces in a space form by a property of the extrinsic shape of circles on hypersurfaces. This characterization corresponds to characterizations of isoparametric hypersurfaces in a space form by properties of the extrinsic shape of geodesics due to Kimura-Maeda.
Toshiaki Adachi, Sadahiro Maeda
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Mathematische Nachrichten, 2023 18 pages, published in Mathematische ...
D'haene, Marie +2 more
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Totally umbilic null hypersurfaces in generalized Robertson–Walker spaces
Differential Geometry and its Applications, 2015 We show that there is a correspondence between totally umbilic null hypersurfaces in generalized Robertson-Walker spaces and twisted decompositions of the fibre. This allows us to prove that nullcones are the unique totally umbilic null hypersurfaces in the closed Friedmann Cosmological model.
Manuel Gutiérrez, Benjamín Olea
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On complete spacelike hypersurfaces with constant scalar curvature in the de Sitter space
Anais da Academia Brasileira de Ciências, 2000 Let Mn be a complete spacelike hypersurface with constant normalized scalar curvature R in the de Sitter Space S1n + 1. Let H the mean curvature and suppose that = (R - 1) > 0 and
ALDIR BRASIL JR, A. GERVASIO COLARES
doaj +1 more source
Lightlike hypersurfaces of an indefinite Kaehler manifold of a quasi-constant curvature [PDF]
, 2019 summary:We study lightlike hypersurfaces $M$ of an indefinite Kaehler manifold $\bar {M}$ of quasi-constant curvature subject to the condition that the characteristic vector field $\zeta $ of $\bar {M}$ is tangent to $M$.
Lee, Jae Won, Jin, Dae Ho
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Totally umbilical hypersurfaces of manifolds admitting a unit Killing field [PDF]
Transactions of the American Mathematical Society, 2012 We prove that a Riemannian product of type M x R (where R denotes the Euclidean line) admits totally umbilical hypersurfaces if and only if M has locally the structure of a warped product and we give a complete description of the totally umbilical hypersurfaces in this case.
Souam, Rabah, Van der Veken, Joeri
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Spacelike Hypersurfaces in Weighted Generalized Robertson‐Walker Space‐Times
Advances in Mathematical Physics, Volume 2018, Issue 1, 2018., 2018 Applying generalized maximum principle and weak maximum principle, we obtain several uniqueness results for spacelike hypersurfaces immersed in a weighted generalized Robertson‐Walker (GRW) space‐time under suitable geometric assumptions. Furthermore, we also study the special case when the ambient space is static and provide some results by using ...
Ximin Liu, Ning Zhang, Remi Léandre
wiley +1 more source