A metric property of umbilic points [PDF]
Anais da Academia Brasileira de Ciências, 2003 In the space of cubic forms of surfaces, regarded as a G-space and endowed with a natural invariant metric, the ratio of umbilic points with a negative index to those with a positive index is evaluated in terms of the asymmetry of the metric, defined ...
Ronaldo Garcia, Jorge Sotomayor
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On the patterns of principal curvature lines around a curve of umbilic points [PDF]
Anais da Academia Brasileira de Ciências, 2005 In this paper is studied the behavior of principal curvature lines near a curve of umbilic points of a smooth surface.Neste trabalho estuda-se o comportamento das linhas de curvatura principal próximas a uma curva de pontos umbílicos, numa superfície ...
Ronaldo Garcia, Jorge Sotomayor
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A study of horizontally weakly conformal maps and their distributions [PDF]
ریاضی و جامعه, 2023 The aim of this paper is to consider horizontally weakly conformal maps which have been studied in [P. Baird and J. C. Wood, Harmonic morphisms between Riemannian manifolds, London Mathematical Society Monographs.
Mehran Aminian
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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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Umbilic and Tangential Singularities on Configurations of Principal Curvature Lines
Anais da Academia Brasileira de Ciências, 2002 In this paper is studied the relationship between quadratic tangencies of principal lines with the boundary of a surface and the Darbouxian umbilics of a smooth boundaryless surface which approximates it through the process of thickening and smoothing ...
RONALDO GARCIA, JORGE SOTOMAYOR
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Shape operator of an $ (n-1) $-dimensional distribution on an $ n $-dimensional manifold and their classification [PDF]
ریاضی و جامعهThis paper aims to study of shape operator of an $ (n-1) $-dimensional distribution on an $ n $-dimensional smooth manifold. In this study firstly we state formulae for the shape operator and its symmetric and anti-symmetric components and in ...
Mehran Aminian, Mehran Namjoo
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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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SLICE: SPT-CL J0546-5345—A Prominent Strong-lensing Cluster at z = 1.07
The Astrophysical Journal LettersMassive galaxy clusters act as prominent strong lenses. Due to a combination of observational biases, cluster evolution, and lensing efficiency, most of the known cluster lenses lie typically at z _l ∼ 0.2–0.7, with only a few prominent examples at ...
Joseph F. V. Allingham +17 more
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Image formation near hyperbolic umbilic in strong gravitational lensing
The Open Journal of AstrophysicsHyperbolic umbilic (HU) is a point singularity of the gravitational lens equation, giving rise to a ring-shaped image formation made of four highly magnified images, off-centred from the lens centre.
Ashish Kumar Meena, Jasjeet Singh Bagla
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Discrete cyclic systems and circle congruences. [PDF]
Ann Mat Pura Appl, 2022 Hertrich-Jeromin U, Szewieczek G.
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