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Homothetic perfect fluid spacetimes [PDF]
Classical and Quantum Gravity, 1997 A brief summary of results on homotheties in General Relativity is given, including general information about space-times admitting an r-parameter group of homothetic transformations for r>2, as well as some specific results on perfect fluids. Attention is then focussed on inhomogeneous models, in particular on those with a homothetic group $H_4 ...
Carot, J., Sintes, A. M.
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Results in Physics, 2021 Static perfect fluid spaces are of great interest in metric theories of gravitation, they being used in building realistic models of some compact objects, like neutron stars and white dwarfs.
Sharief Deshmukh +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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In search of the perfect fluid [PDF]
AIP Conference Proceedings, 2009 4 pages, prepared for the proceedings of CIPANP 09, San Diego, USA, March 26-31 ...
Thomas Schäfer, Marvin L. Marshak
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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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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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Mathematical Formalism in Cosmological Models of Gravity
Semina: Ciências Exatas e Tecnológicas, 2016 We analyze solutions to Friedmann-Robertson-Walker cosmologies in Brans-Dicke theory, where a scalar field is coupled to gravity. The cosmological solutions of Brans-Dicke theory, characterized by a decaying vacuum energy density and by a constant ...
Artigo Retratado
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The Newtonian Limit for Perfect Fluids [PDF]
Communications in Mathematical Physics, 2007 We prove that there exists a class of non-stationary solutions to the Einstein-Euler equations which have a Newtonian limit. The proof of this result is based on a symmetric hyperbolic formulation of the Einstein-Euler equations which contains a singular parameter $\ep = v_T/c$ where $v_T$ is a characteristic velocity scale associated with the fluid ...
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Perfect fluid spacetimes and $k$-almost Yamabe solitons
, 2023 In this article, we presumed that a perfect fluid is the source of the gravitational field while analyzing the solutions to the Einstein field equations.
De, Krishnendu +5 more
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Perfect fluid spacetimes, Gray's decomposition and $f(\mathcal{R}, {T})$-gravity [PDF]
, 2022 In this paper, first we give the complete classifications of perfect fluid spacetimes under the Gray’s decomposition. Then we investigate the condition under which the Ricci tensor is a conformal Killing tensor in a perfect fluid spacetime.
U.c. DE +4 more
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