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Related papers: Bianchi Models with Chaplygin Gas

200 papers

An exact cosmological solution of Einstein field equations (EFEs) is derived for a dynamical vacuum energy in $f(R,T)$ gravity for Friedmann-Lemaitre-Robertson-Walker (FLRW) space-time. A parametrization of the Hubble parameter is used to…

General Physics · Physics 2018-11-22 Ritika Nagpal , S. K. J. Pacif , J. K. Singh , Kazuharu Bamba , A. Beesham

The comprehensive formulation for loop quantum cosmology in the spatially flat, isotropic model was recently constructed. In this paper, the methods are extended to the anisotropic Bianchi I cosmology. Both the precursor and the improved…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Dah-Wei Chiou

The phase space of Bianchi I universes in vacuum Brans-Dicke gravity is analyzed in terms of physical variables. The behaviour of the solutions of the field equations near the fixed points (which are solutions of Einstein gravity) is…

General Relativity and Quantum Cosmology · Physics 2024-05-01 Julien Houle , Valerio Faraoni

We investigate a flat Friedmann-Robertson-Walker spacetime filled with k-essence and find the set of functions F which generate three different families of extended tachyon fields and Chaplygin gases. They lead to accelerated and…

Astrophysics · Physics 2009-11-10 Luis P. Chimento

We use the expansion-normalized variables approach to study the dynamics of a non-tilted Bianchi Type I cosmological model with both a homogeneous magnetic field and a viscous fluid. In our model the perfect magnetohydrodynamic…

General Relativity and Quantum Cosmology · Physics 2014-02-26 Ikjyot Singh Kohli , Michael C. Haslam

The generalized Chaplygin gas model, characterized by the equation of state $p = - \frac{B}{\rho^{\alpha}}$, is investigated within the framework of a Robertson-Walker spacetime. The resulting field equations governing this model are highly…

General Relativity and Quantum Cosmology · Physics 2025-07-02 D Panigrahi

In this paper, we discuss the Bianchi type-I cosmological model in the framework of symmetric teleparallel gravity say $f(Q)$ gravity in which the non-metricity term $Q$ is responsible for the gravitational interaction. We consider a…

General Relativity and Quantum Cosmology · Physics 2023-04-05 M. Koussour , S. H. Shekh , M. Govender , M. Bennai

The present study deals with spatially homogeneous and anisotropic Bianchi-I cosmological model representing massive strings. The energy-momentum tensor, as formulated by Letelier (Phys. Rev. D 28: 2414, 1983) has been used to construct…

General Physics · Physics 2014-03-11 Chanchal Chawla , R. K. Mishra , Anirudh Pradhan

We consider the 4+1 Einstein's field equations (EFE's) in vacuum, simplified by the assumption that there is a four-dimensional sub-manifold on which an isometry group of dimension four acts simply transitive. In particular we consider the…

General Relativity and Quantum Cosmology · Physics 2018-07-11 T. Pailas , Petros A. Terzis , T. Christodoulakis

Spatially homogeneous but totally anisotropic and non-flat Bianchi type II cosmological model has been studied in general relativity in the presence of two minimally interacting fluids; a perfect fluid as the matter fluid and a hypothetical…

General Relativity and Quantum Cosmology · Physics 2012-06-18 Suresh Kumar , Ozgur Akarsu

This paper is devoted to investigate the anisotropic locally rotationally symmetric (LRS) Bianchi type-I space-time in the context of the recently proposed $f(Q)$ gravity in which $Q$ is the non-metricity scalar. For this purpose, we…

General Relativity and Quantum Cosmology · Physics 2022-08-26 M. Koussour , K. El Bourakadi , S. H. Shekh , S. K. J. Pacif , M. Bennai

Bianchi type V bulk viscous fluid cosmological models are investigated with dynamic cosmological term $\Lambda(t)$. Using a generation technique (Camci {\it et al.}, 2001), it is shown that the Einstein's field equations are solvable for…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Anirudh Pradhan , Kanti Jotania , Anju Rai

The paper presents some exact solutions of Bianchi types I, III and Kantowski-Sachs cosmological models consisting of a dissipative fluid along with an axial magnetic field. A barytropic equation of state between the thermodynamic pressure…

General Relativity and Quantum Cosmology · Physics 2021-05-18 A. Banerjee , Abhik Kumar Sanyal

We employ the generalized Chaplygin gas of interacting dark energy to obtain the equation of state for the generalized Chaplygin gas energy density in non-flat universe. By choosing a negative value for $B$ we see that $w_{\rm…

General Relativity and Quantum Cosmology · Physics 2010-10-27 M R Setare

We develop approximation methods in the hybrid quantization of the Gowdy model with linear polarization and a massless scalar field, for the case of three-torus spatial topology. The loop quantization of the homogeneous gravitational sector…

General Relativity and Quantum Cosmology · Physics 2014-12-01 Mercedes Martín-Benito , Daniel Martín-de Blas , Guillermo A. Mena Marugán

By using Bianchi I type of homogenous and anisotropic background metric having cylindrical symmetry in $x$ direction of a local cartesian coordinates system, we solve metric field equations for a non-minimally coupled Einstein-Maxwell…

General Relativity and Quantum Cosmology · Physics 2020-12-08 Hossein Ghaffarnejad , Hoda Gholipour

The Einstein equations for one of the hypersurface-homogeneous rotating dust models are investigated. It is a Bianchi type V model in which one of the Killing fields is spanned on velocity and rotation (case 1.2.2.2 in the classification…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Andrzej Krasinski

We try to answer the question whether the quantized free scalar field on a spatially flat Friedmann-Robertson-Walker (FRW) spacetime is a matter model that can induce a Chaplygin gas equation of state. For this purpose we first describe how…

General Relativity and Quantum Cosmology · Physics 2013-08-05 Jan Zschoche

In this paper, we report the existence of transitioning scenario of Bianchi type I universe in the context of $f\left(R,T\right)$ gravity with special case $f\left(R,T\right) = f_{1}(R) + f_{2}(R)f_{3}(T)$ and it's functional forms…

General Physics · Physics 2019-04-24 Anil Kumar Yadav

We study the static cosmological solutions and their stability at background level in the framework of massive bigravity theory with Friedmann-Robertson-Walker (FRW) metrics. By the modification proposed in the cosmological equations…

General Relativity and Quantum Cosmology · Physics 2017-05-17 M. Mousavi , F. Darabi