Results 1 to 10 of about 1,153 (77)
Evolutoids and pedaloids of frontals on timelike surfaces
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
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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Length functions in Teichmüller and anti-de Sitter geometry
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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Comparison Theorems on Weighted Finsler Manifolds and Spacetimes with ϵ-Range
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
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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Isometry Lie algebras of indefinite homogeneous spaces of finite volume
Abstract Let g be a real finite‐dimensional Lie algebra equipped with a symmetric bilinear form ⟨·,·⟩. We assume that ⟨·,·⟩ is nil‐invariant. This means that every nilpotent operator in the smallest algebraic Lie subalgebra of endomorphisms containing the adjoint representation of g is an infinitesimal isometry for ⟨·,·⟩.
Oliver Baues+2 more
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On Carleman and observability estimates for wave equations on time‐dependent domains
Abstract We establish new Carleman estimates for the wave equation, which we then apply to derive novel observability inequalities for a general class of linear wave equations. The main features of these inequalities are that (a) they apply to a fully general class of time‐dependent domains, with timelike moving boundaries, (b) they apply to linear ...
Arick Shao
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Screen conformal half‐lightlike submanifolds
We study some properties of a half‐lightlike submanifold M, of a semi‐Riemannian manifold, whose shape operator is conformal to the shape operator of its screen distribution. We show that any screen distribution S(TM) of M is integrable and the geometry of M has a close relation with the nondegenerate geometry of a leaf of S(TM).
K. L. Duggal, B. Sahin
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In this paper, we discuss the monotonicity of the first nonzero eigenvalue of the Laplace operator and the p-Laplace operator under a forced mean curvature flow (MCF).
Qi Xuesen, Liu Ximin
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Trajectories under a vectorial potential on stationary manifolds
By using variational methods, we study the existence and multiplicity of trajectories under a vectorial potential on (standard) stationary Lorentzian manifolds possibly with boundary.
Rossella Bartolo
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