Results 21 to 30 of about 519,784 (286)
Cosmological constant as Hyper Geometric function in fivedimensional space-time
Journal of Applied Science and Engineering, 2023 In this paper, we have studied the Einstein Field equation in Kaluza-Klein space-time in five dimension with the metric dS^2 = dt^2 − A^2(dx^2 + dy^2 + dz^2)− B^2dψ^2 under the assumption that B = αt, where α = Constant and scale factor satisfying the ...
Satish T. Rathod, Kalpana Pawar
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Graphene: A Nearly Perfect Fluid [PDF]
Physical Review Letters, 2009 Hydrodynamics and collision-dominated transport are crucial to understand the slow dynamics of many correlated quantum liquids. The ratio eta/s of the shear viscosity eta to the entropy density s is uniquely suited to determine how strongly the excitations in a quantum fluid interact. We determine eta/s in clean undoped graphene using a quantum kinetic
Markus, Müller +2 more
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A Non-Polynomial Gravity Formulation for Loop Quantum Cosmology Bounce
Galaxies, 2017 Recently the so-called mimetic gravity approach has been used to obtain corrections to the Friedmann equation of General Relativity similar to the ones present in loop quantum cosmology.
Stefano Chinaglia +2 more
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Cylindrically symmetric perfect-fluid universes [PDF]
, 2000 The aim of this paper is to examine some obtained exact solutions of the Einstein-Maxwell equations, especially their properties from a chronological point of view.
Banerjee A +9 more
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Physics Letters B, 2010 7 pages, 5 figures, To appear in Phys. Lett. B (2010)
Rahaman, F. +4 more
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Perfect fluid spacetimes with two symmetries [PDF]
Classical and Quantum Gravity, 2004 A method of solving perfect fluid Einstein equations with two commuting spacelike Killing vectors is presented. Given a spacelike 2-dimensional surface in the 3-dimensional nonphysical Minkowski space the field equations reduce to a single nonlinear differential equation. An example is discussed.
Szereszewski, A., Tafel, J.
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Mathematics, 2022 Sufficient conditions for a Lorentzian generalized quasi-Einstein manifold M,g,f,μ to be a generalized Robertson–Walker spacetime with Einstein fibers are derived. The Ricci tensor in this case gains the perfect fluid form.
Sameh Shenawy +3 more
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Axistationary perfect fluids - a tetrad approach [PDF]
Classical and Quantum Gravity, 1999 12 ...
Fodor, Gyula +2 more
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A classification of scalar field potentials with cosmological scaling solutions [PDF]
, 1998 An attractive method of obtaining an effective cosmological constant at the present epoch is through the potential energy of a scalar field. Considering models with a perfect fluid and a scalar field, we classify all potentials for which the scalar field
Liddle, Andrew R, Scherrer, Robert J
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Frontiers in Astronomy and Space Sciences, 2022 Within the context of Saez-Ballester theory, we explored the interaction of a five-dimensional Bianchi type-I anisotropic cloud string cosmological model Universe with an electromagnetic field. With an electromagnetic field, the energy momentum tensor is
Jagat Daimary, Rajshekhar Roy Baruah
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