Results 11 to 20 of about 1,515,012 (182)
PERFECT FLUID SPACETIMES WITH HARMONIC GENERALIZED CURVATURE TENSOR [PDF]
Osaka Journal of Mathematics, 2019 We show that n-dimensional perfect fluid spacetimes with divergence-free conformal curva- ture tensor and constant scalar curvature are generalized Robertson Walker (GRW) spacetimes; as a consequence a perfect fluid Yang pure space is a GRW spacetime.
C. A. Mantica +3 more
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Geometry of Twisted Products and Applications on Static Perfect Fluid Spacetimes [PDF]
International Electronic Journal of Geometry, 2023 In this paper, first we study the harmonicity of the functions and forms on the twisted products, and then we determine its sectional curvature. We explore some characteristics of static perfect fluid and static vacuum spacetimes on twisted product manifolds by proving the existence and obstructions on Ricci curvature. Finally, we study the problem
Güler, Sinem +3 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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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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Infinite Kinematic Self-Similarity and Perfect Fluid Spacetimes [PDF]
General Relativity and Gravitation, 2001 38 pages, 6 figures.
Sintes, A., Benoit, P., Coley, A.
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Some curvature properties of perfect fluid spacetimes [PDF]
Quaestiones Mathematicae, 2023 In this paper we assume that a perfect fluid is the source of the gravitational field while analyzing the solutions to the Einstein field equations.
Krishnendu De +2 more
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The Spacetime Geodesy of Perfect Fluid Spheres
SymmetryHerein we shall argue for the utility of “spacetime geodesy”, a point of view where one delays as long as possible worrying about dynamical equations, in favour of the maximal utilization of both symmetries and geometrical features. This closely parallels Weinberg’s distinction between “cosmography” and “cosmology”, wherein maximal utilization of both ...
Christopher Simmonds, Matt Visser
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Sufficient conditions for a pseudosymmetric spacetime to be a perfect fluid spacetime [PDF]
International Journal of Geometric Methods in Modern Physics, 2021 The aim of this paper is to obtain the condition under which a pseudosymmetric spacetime to be a perfect fluid spacetime. It is proven that a pseudosymmetric generalized Robertson–Walker spacetime is a perfect fluid spacetime. Moreover, we establish that a conformally flat pseudosymmetric spacetime is a generalized Robertson–Walker spacetime. Next, it
Peibiao Zhao +3 more
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Spacetimes Admitting Concircular Curvature Tensor in f(R) Gravity
Frontiers in Physics, 2022 The main object of this paper is to investigate spacetimes admitting concircular curvature tensor in f(R) gravity theory. At first, concircularly flat and concircularly flat perfect fluid spacetimes in fR gravity are studied.
Uday Chand De +5 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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