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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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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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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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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Interior spacetimes sourced by stationary differentially rotating irrotational cylindrical fluids. Perfect fluids [PDF]
, 2023 International audienceIn a recent series of papers new exact analytical solutions of the Einstein equations representing interior spacetimes sourced by stationary rigidly rotating cylinders of different kinds of fluids have been displayed, Célérier, Phys.
Célérier, Marie-Noëlle
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Characterizations of Perfect fluid spacetimes obeying $f(\mathcal{R})$-gravity equipped with different gradient solitons [PDF]
, 2022 The prime object of this article is to study the perfect fluid spacetimes obeying $f(\mathcal{R})$-gravity, when $\eta$-Ricci solitons, gradient $\eta$-Ricci solitons, gradient Einstein Solitons and gradient $m$-quasi Einstein solitons are its metrics ...
Suh, Krishnendu De Young Jin +1 more
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On Bianchi Type VI Spacetimes with Orthogonal Perfect Fluid Matter [PDF]
, 2020 We study the asymptotic behaviour of Bianchi type VI0 spacetimes with orthogonal perfect fluid matter satisfying Einstein’s equations. In particular, we prove a conjecture due to Wainwright about the initial singularity on such backgrounds.
Oude Groeniger, Johannes,
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On the initial singularity and extendibility of flat quasi-de Sitter spacetimes
Journal of High Energy Physics, 2023 Inflationary spacetimes have been argued to be past geodesically incomplete in many situations. However, whether the geodesic incompleteness implies the existence of an initial spacetime curvature singularity or whether the spacetime may be extended ...
Ghazal Geshnizjani +2 more
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European Physical Journal C: Particles and Fields, 2023 We investigate the existence of anisotropic self-similar exact solutions in symmetric teleparallel $$f\left( Q\right) $$ f Q -theory. For the background geometry we consider the Kantowski–Sachs and the Locally Rotationally Symmetric Bianchi type III ...
N. Dimakis +3 more
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Islands in the fluid: islands are common in cosmology
Journal of High Energy Physics, 2023 We discuss the possibility of entanglement islands in cosmological spacetimes with a general perfect fluid with an equation of state w. We find that flat universes with time-symmetric slices where the Hubble parameter vanishes always have islands on that
Ido Ben-Dayan +2 more
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