Results 61 to 70 of about 17,898 (118)
Maximum Principle for Totally Umbilical Null Hypersurfaces and Time-dependent Null Horizons
Journal of Mathematics Research, 2015 In this paper we modify the maximum principal of (Galloway, 2000) for totally geodesic null hypersurfaces by proving a geometric maximum principle which obeys mean curvature inequalities of a family of totally umbilical null hypersurfaces of a spacetime manifold (Theorem~6).
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Chen's Ricci inequalities and topological obstructions on null hypersurfaces of a Lorentzian manifold. [PDF]
J Inequal Appl, 2018 Ménédore K.
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Gap phenomenon of an abstract Willmore type functional of hypersurface in unit sphere. [PDF]
ScientificWorldJournal, 2014 Zhu Y, Liu J, Wu G.
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Totally Umbilical Hypersurfaces of Kaehler Manifolds
Totally Umbilical Hypersurfaces of Kaehler Manifolds24 KJ00003571949 論文 ...
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, 2014 In this paper we study curvature properties of semi-symmetric type of totally umbilical radical transversal lightlike hypersurfaces $(M,g)$ and $(M,\widetilde g)$ of a Kähler-Norden manifold $(\overline M,\overline J,\overline g,\overline {\widetilde g})$ of constant totally real sectional curvatures $\overline ν$ and $\overline {\widetilde ν}$ ($g ...
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Annals of Global Analysis and GeometryAbstractWe study the effects of the null energy condition on totally umbilic hypersurfaces in a class of static spacetimes, both in the spacelike and the timelike case, respectively. In the spacelike case, we study totally umbilic warped product graphs and give a full characterization of embedded surfaces with constant spacetime mean curvature using an
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Codazzi and totally umbilical hypersurfaces in Sol1 4
Codazzi and totally umbilical hypersurfaces in Sol1 4In this paper, we prove the non-existence of Codazzi and totally umbilical hypersurfaces, especially totally geodesic hypersurfaces, in the 4-dimensional model space Sol(1)(4).
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Totally umbilic null hypersurfaces in generalized Robertson-Walker spaces
, 2018 Using a correspondence between totally umbilic null hypersurfaces in generalized Robertson-Walker spaces and twisted decompositions of the fibre we show that nullcones are the unique totally umbilic null hypersurfaces in the closed Friedmann Cosmological model and a uniqueness result for dual pairs of totally umbilic null hypersurfaces in Reissner ...
Gutiérrez López, Manuel +5 more
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Totally umbilical surfaces in normal contact Riemannian manifolds
, 1967 Yoshiko Watanabe
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Foliations of lightlike hypersurfaces and their physical interpretation
Open Mathematics, 2012 Duggal Krishan
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