Results 11 to 20 of about 7,610 (173)
Semiconformal curvature tensor and perfect fluid spacetimes in general relativity
Journal of Taibah University for Science, 2020 The semiconformal curvature tensor and its divergence have been studied for perfect fluid spacetimes. It is seen, apart from other results, that the perfect fluid spacetimes with divergence-free semiconformal curvature tensor either satisfy the vacuum ...
Musavvir Ali +2 more
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Isotropic Cosmological Singularities: I. Polytropic Perfect Fluid Spacetimes [PDF]
Annals of Physics, 1999 The conformal Einstein equations for polytropic perfect fluids cosmologies which admit an isotropic singularity are considered. It is proved that the Cauchy problem in this case is well posed, that is, that solution exist, are unique an depend smoothly on the initial data of the 3- surface of the singularity.
Anguige, K., Tod, K. P.
exaly +5 more sources
Hyperbolic Ricci solitons on perfect fluid spacetimes
AIMS Mathematics<abstract><p>In the present paper, we investigate perfect fluid spacetimes and perfect fluid generalized Roberston-Walker spacetimes that contain a torse-forming vector field satisfying almost hyperbolic Ricci solitons. We show that the perfect fluid spacetimes that contain a torse-forming vector field satisfy an almost hyperbolic Ricci ...
Shahroud Azami +3 more
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On some non-static plane symmetric perfect fluid solutions in f(R,T) gravity
Results in Physics, 2022 We address the problem of finding non-static plane symmetric perfect fluid solutions in the f(R,T)theory of gravity, where R and T respectively are the Ricci scalar and trace of the energy momentum tensor.
Abu Bakr Mehmood +5 more
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Conformally Flat Pseudoprojective Symmetric Spacetimes in fR,G Gravity
Advances in Mathematical Physics, 2022 Sufficient conditions on a pseudoprojective symmetric spacetime PPSn whose Ricci tensor is of Codazzi type to be either a perfect fluid or Einstein spacetime are given.
Uday Chand De +3 more
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Perfect fluid spacetimes and $k$-almost Yamabe solitons
Turkish Journal of Mathematics, 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. With this new and creative approach, here we study $k$-almost yamabe solitons and gradient $k$-almost yamabe solitons.
De, Krishnendu +2 more
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Investigation of Pseudo-Ricci Symmetric Spacetimes in Gray’s Subspaces
Journal of Mathematics, 2021 In the present paper, we focused our attention to study pseudo-Ricci symmetric spacetimes in Gray’s decomposition subspaces. It is proved that PRSn spacetimes are Ricci flat in trivial, A, and B subspaces, whereas perfect fluid in subspaces I, I⊕A, and I⊕
Sameh Shenawy +4 more
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Wormholes, killing horizons and naked singularities: light surfaces in axially symmetric spacetimes
European Physical Journal C: Particles and Fields, 2022 We study several classes of exterior and interior axially symmetric spacetimes, such as wormholes, accelerating black holes, and binary black hole systems, from the point of view of light surfaces related to the generators of Killing horizons.
D. Pugliese, H. Quevedo
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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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Conharmonic Curvature Inheritance in Spacetime of General Relativity
Universe, 2021 The motive of the current article is to study and characterize the geometrical and physical competency of the conharmonic curvature inheritance (Conh CI) symmetry in spacetime.
Musavvir Ali +2 more
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