Results 51 to 60 of about 264 (216)
Rotating traversable wormholes in Einstein-Maxwell theory
Physics Letters B, 2023 It is well-known that traversable wormhole solutions to the Einstein equations require the existence of an exotic matter source violating the null energy condition. An apparent exception is the overcharged Kerr-Newman-NUT solution of the Einstein-Maxwell
Gérard Clément, Dmitri Gal'tsov
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On Closed Geodesics in Lorentz Manifolds
Geometric and Functional AnalysisAbstractWe construct compact Lorentz manifolds without closed geodesics.
Souheib Allout +2 more
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Advanced Intelligent Systems, EarlyView.A hybrid mobile robot with a modular Variable‐Stiffness Bridge transitions between a rigid locomotion platform and a flexible, shape‐conforming body. By enclosing objects within its deformable structure rather than relying on dedicated end effectors, the robot achieves orientation‐regulated planar transport, with conformal contact quality shown to ...
Luiza Labazanova +5 more
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American Journal of Botany, EarlyView.Abstract Premise Desert plant assemblages in southern California provide an opportunity to link patterns of community structure with climate‐driven vulnerability in a rapidly changing environment. California sustains an exceptionally diverse flora of approximately 4300 plant species, with 31% identified as endemic.
Hector Zumbado‐Ulate +4 more
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The Global Attractor of the Allen-Cahn Equation on the Sphere
Frontiers in Applied Mathematics and Statistics, 2020 In this paper we study the attractor of a parabolic semiflow generated by a singularly perturbed PDE with a non-linear term given by a bistable potential, in an oval surface; the Allen-Cahn equation being a prototypical example.
David Medina, Pablo Padilla
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Closed geodesics in dilation surfaces
Geometry & TopologyWe prove that directions of closed geodesics in every dilation surface form a dense subset of the circle. The proof draws on a study of the degenerations of the Delaunay triangulation of dilation surfaces under the action of Teichmüller flow in the moduli space.
Boulanger, Adrien +2 more
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Bifurcation of Closed Geodesics
Geometry, Integrability and Quantization, 2018 This paper is denoted to further study of geodesic bifurcation on surfaces of revolution. We demonstrate an example of bifurcation of closed geodesics on surfaces.
Rýparová, Lenka, Mikeš, Josef
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Annals of Neurology, EarlyView.Objective Amyotrophic lateral sclerosis (ALS) has a markedly distinctive clinical and neuroradiological signature, with the preferential involvement of specific brain networks and the apparent sparing of others. The molecular underpinnings of the strikingly selective anatomical vulnerability have not been fully elucidated to date despite the potential ...
Marlene Tahedl +10 more
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Sensors, 2023 In this paper, we investigate the algorithms for traversal exploration and path coverage of target regions using multiple agents, enabling the efficient deployment of a set of agents to cover a complex region.
Yijie Qin +3 more
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Closed timelike geodesics [PDF]
Transactions of the American Mathematical Society, 1984 It is shown that every stable free t t -homotopy class of closed timelike curves in
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