Results 1 to 10 of about 1,037 (71)
Evolutoids and pedaloids of frontals on timelike surfaces
Open Mathematics, 2023 In this article, we define evolutoids and pedaloids of frontals on timelike surfaces in Minkowski 3-space. The evolutoids of frontals on timelike surfaces are not only the generalization of evolutoids of curves in the Minkowski plane but also the ...
Wang Yongqiao +3 more
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Mannheim curves and their partner curves in Minkowski 3-space E13
Demonstratio Mathematica, 2022 The modified orthogonal frame is an important tool to study analytic space curves whose curvatures have discrete zero points. In this article, by using the modified orthogonal frame, Mannheim curves and their partner curves are investigated in Minkowski ...
Elsharkawy Ayman, Elshenhab Ahmed M.
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Comparison Theorems on Weighted Finsler Manifolds and Spacetimes with ϵ-Range
Analysis and Geometry in Metric Spaces, 2022 We establish the Bonnet–Myers theorem, Laplacian comparison theorem, and Bishop–Gromov volume comparison theorem for weighted Finsler manifolds as well as weighted Finsler spacetimes, of weighted Ricci curvature bounded below by using the weight function.
Lu Yufeng +2 more
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Spacelike Bertrand curves in Minkowski 3-space revisited
Analele Stiintifice ale Universitatii Ovidius Constanta: Seria Matematica, 2023 In the geometry of curves in 𝔼3, if the principal normal vector field of a given space curve ϕ with non-zero curvatures is the principal normal vector field of another space curve ϕ*, then the curve ϕ is called a Bertrand curve and ϕ* is called Bertrand ...
Erdem Hatice Altın, İlarslan Kazım
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Length functions in Teichmüller and anti-de Sitter geometry
Forum of Mathematics, Sigma, 2023 We establish a link between the behavior of length functions on Teichmüller space and the geometry of certain anti-de Sitter $3$ -manifolds. As an application, we give new purely anti-de Sitter proofs of results of Teichmüller theory such as ...
Filippo Mazzoli, Gabriele Viaggi
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Quantum cosmological Friedman models with a Yang-Mills field and positive energy levels [PDF]
, 2010 We prove the existence of a spectral resolution of the Wheeler-DeWitt equation when the matter field is provided by a Yang-Mills field, with or without mass term, if the spatial geometry of the underlying spacetime is homothetic to $\R[3]$.
Claus Gerhardt +3 more
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Helices in the n-dimensional Minkowski spacetime
Results in Physics, 2019 In this work, we find position vectors of non-null helices in the n-dimensional Minkowski spacetime. We present methods to generate helices from polynomial curves.
Bulent Altunkaya
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A new approach on helices in pseudo-Riemannian manifolds [PDF]
, 2013 In this paper, we give a definition of harmonic curvature functions in terms of V_{n} and define a new kind of slant helix which is called V_{n}-slant helix in n-dimensional pseudo-Riemannian manifold.
Gök, İsmail +2 more
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Algebraic Properties of Curvature Operators in Lorentzian Manifolds with Large Isometry Groups [PDF]
, 2010 Together with spaces of constant sectional curvature and products of a real line with a manifold of constant curvature, the socalled Egorov spaces and $\varepsilon$-spaces exhaust the class of $n$-dimensional Lorentzian manifolds admitting a group of ...
Calvaruso, Giovanni, Garcia-Rio, Eduardo
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A condition for a perfect-fluid space-time to be a generalized Robertson-Walker space-time [PDF]
, 2016 A perfect-fluid space-time of dimension n>3 with 1) irrotational velocity vector field, 2) null divergence of the Weyl tensor, is a generalised Robertson-Walker space-time with Einstein fiber. Condition 1) is verified whenever pressure and energy density
De, Uday Chand +2 more
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