Results 21 to 30 of about 384 (243)
On parabolic and umbilic points of immersed hypersurfaces [PDF]
Transactions of the American Mathematical Society, 1967 Introduction. This paper is a natural sequel to Geometry of immersions. I and II ([1] and [2]). The object is to apply the general geometric singularity theory developed in [1] and [2] to two specific geometric singularities of an immersed n manifold in R'+ll.
E. A. Feldman
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Umbilicity of (Space-Like) Submanifolds of Pseudo-Riemannian Space Forms [PDF]
Journal of Sciences, Islamic Republic of Iran, 2009 We study umbilic (space-like) submanifolds of pseudo-Riemannian space forms, then define totally semi-umbilic space-like submanifold of pseudo Euclidean space and relate this notion to umbilicity.
S.M.B. Kashani
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Degenerate Umbilic Points of Analytic Surfaces
Umbilics are points of a surface embedded in three space where normal curvatures are independent of direction. The (in)famous Carathéodory Conjecture states that a compact simply connected embedded surface has at least two umbilic points. A counterexample to this conjecture would be a surface whose principal foliation has index two at a single umbilic.
Guckenheimaer, John
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Characterizations of Umbilic Points of Isometric Immersions in Riemannian and Lorentzian Manifolds
Taiwanese Journal of Mathematics, 2016 Several characterizations of umbilic points of submanifolds in arbitrary Riemannian and Lorentzian manifolds are given. As a consequence, we obtain new characterizations of spheres in the Euclidean space and of hyperbolic spaces in the Lorentz-Minkowski space. We also prove the Lorentzian version of a classical result by Cartan.
Caballero, Magdalena +1 more
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Bifurcation of solutions through a contact manifold in bidisperse models
Frontiers in Applied Mathematics and Statistics, 2023 This research focuses on a hyperbolic system that describes bidisperse suspensions, consisting of two types of small particles dispersed in a viscous fluid.
Stefan Berres, Pablo Castañeda
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On isolated umbilic points [PDF]
Communications in Analysis and Geometry, 2020 Counter-examples to the famous conjecture of Caratheodory, as well as the bound on umbilic index proposed by Hamburger, are constructed with respect to Riemannian metrics that are arbitrarily close to the flat metric on Euclidean 3-space. In particular, Riemannian metrics with a smooth strictly convex 2-sphere containing a single umbilic point are ...
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Planar Sections of a Surface Close to an Umbilic [PDF]
, 2022 We study the intersection between a smooth algebraic surface with an umbilic point and a plane parallel and close to the tangent plane at the umbilic.
Pukhlikov, Aleksandr +3 more
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Umbilic Points and Special Curves on Surfaces in Minkowski Space
, 2021 O estudo de superfícies no espaço Minkowski apresenta diferenças com relação ao caso Euclidiano. A mudança na primeira forma fundamental cria pontos onde a métrica pode se degenerar e pontos onde as direções principais coincidem.
Fernandes, Marco Antônio do Couto
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Structurally stable configurations of lines of mean curvature and umbilic points on surfaces immersed in R3 [PDF]
, 2001 In this paper we study the pairs of orthogonal foliations on oriented surfaces immersed in R3 whose singularities and leaves are, respectively, the umbilic points and the lines of normal mean curvature of the immersion.
Sotomayor, Jorge +3 more
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Correlations and screening of topological charges in Gaussian random fields [PDF]
, 2003 Two-point topological charge correlation functions of several types of geometric singularity in Gaussian random fields are calculated explicitly, using a general scheme: zeros of n-dimensional random vectors, signed by the sign of their Jacobian ...
Dennis, MR +2 more
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