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The energy density of the universe is proportional to the Ricci scalar curvature in the dynamical Chern-Simon (CS) modified gravity. In this paper, we consider the Amended Friedman-Robertson-Walker (AFRW) universe and explore its scale…

General Relativity and Quantum Cosmology · Physics 2015-09-21 M. Jamil Amir , Sarfraz Ali

In order to account for the observed cosmic acceleration, a modification of the ansatz for the variation of density in Friedman-Robertson-Walker (FRW) models given by Islam is proposed. The modified ansatz leads to an equation of state…

General Physics · Physics 2017-11-13 Abdussattar , S R Prajapati

In this paper, we derive the field equations of modified Gauss-Bonnet gravity termed as $f(R,G)$ gravity for the non-flat Friedmann-Robertson-Walker (FRW) spacetime. We utilize the dynamical system approach to study the cosmic dynamics of…

General Relativity and Quantum Cosmology · Physics 2025-01-22 Ashutosh Singh

Analysis of the gravitational source for the Schwarzschild metric indicates that the time and the radial components of the energy momentum tensor are equal. Imposing such a condition on cosmology, we propose a cosmological model that is a…

Astrophysics · Physics 2007-05-23 Yukio Tomozawa

A flat FLRW cosmological model with perfect fluid comprising of variable Chaplygin gas has been studied in context of f(R; T) gravity with particle creation. The considered scale factors describe the accelerated expansion of universe due to…

General Relativity and Quantum Cosmology · Physics 2020-02-12 N. Hulke , G. P. Singh , Binaya K. Bishi , A. Singh

We present a Friedmann-Robertson-Walker quantum cosmological model in the presence of Chaplygin gas and perfect fluid for early and late time epoches. In this work, we consider perfect fluid as an effective potential and apply Schutz's…

General Relativity and Quantum Cosmology · Physics 2008-11-26 P. Pedram , S. Jalalzadeh

The evolution of a universe modelled as a mixture of generalised Chaplygin gas and ordinary matter field is studied for a Robertson Walker type of spacetime. This model could interpolate periods of a radiation dominated, matter dominated…

General Relativity and Quantum Cosmology · Physics 2017-02-14 D. Panigrahi , S. Chatterjee

The Friedmann-Robertson-Walker(FRW) model with dynamical Dark Energy(DE) in the form of modified Chaplygin gas(MCG) has been investigated. The evolution equations are reduced to an autonomous system on the two dimensional phase plane and it…

General Relativity and Quantum Cosmology · Physics 2015-05-28 Nairwita Mazumder , Ritabrata Biswas , Subenoy Chakraborty

A spatially flat Friedmann-Robertson-Walker(FRW) cosmological model with generalized Chaplygin gas is studied in the context of scalar-metric formulation of cosmology. Schutz's mechanism for the perfect fluid is applied with generalized…

General Relativity and Quantum Cosmology · Physics 2011-06-24 Barun Majumder

We analyze the global nonlinear stability of FRW (Friedmann-Robertson-Walker) spacetimes in presence of an irrotational perfect fluid. We assume that the fluid is governed by the so-called (generalized) Chaplygin equation of state relating…

General Relativity and Quantum Cosmology · Physics 2015-12-14 Philippe G. LeFloch , Changhua Wei

In this work, we have considered the Friedmann-Robertson-Walker (FRW) model of the universe where bounce occurs and the universe is filled with Generalized Cosmic Chaplygin Gas (GCCG) or Variable Modified Chaplygin Gas (VMCG). We have…

General Relativity and Quantum Cosmology · Physics 2018-12-11 Tanwi Bandyopadhyay , Ujjal Debnath

In this paper, we have studied $F(R,T)$ gravity as an arbitrary function of curvature and torsion scalars in Friedmann--Lema\^{\i}tre--Robertson--Walker (FLRW) background. Then, we have considered interacting model between $F(R,T)$ gravity…

General Relativity and Quantum Cosmology · Physics 2023-07-19 Ali R. Amani , S. L. Dehneshin

We study the condition for the consistency of the G\"{o}del metric with the dynamical Chern-Simons modified gravity. It turns out to be that this compatibility can be achieved only if the cosmological constant is variable in the space.

High Energy Physics - Theory · Physics 2015-03-17 C. Furtado , J. R. Nascimento , A. Yu. Petrov , A. F. Santos

Cosmological redshift z grows as the Universe expands and is conventionally viewed as a third form of redshift, beyond the more traditional Doppler and gravitational effects seen in other applications of general relativity. In this paper,…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-26 Fulvio Melia

In this paper, we study in Friedmann-Robertson-Walker universe the interaction between the viscous generalized Chaplygin gas with $f(R,T)$ gravity, which is an arbitrary function of the Ricci scalar $R$ and the trace $T$ of the…

General Relativity and Quantum Cosmology · Physics 2017-05-11 E. H. Baffou , I. G. Salako , M. J. S. Houndjo

General relativity is extended by promoting the three-dimensional gravitational Chern-Simons term to four dimensions. This entails choosing an embedding coordinate v_\mu -- an external quantity, which we fix to be a non-vanishing constant…

General Relativity and Quantum Cosmology · Physics 2014-11-17 R. Jackiw , S. -Y. Pi

In this work the role of extra dimensions in the accelerated universe through the scenario of higher-dimensional Friedmann-Robertson-Walker (FRW) cosmology has been studied. For this purpose, we first consider warped space-time in the…

Cosmology and Nongalactic Astrophysics · Physics 2013-07-15 M. Mohsenzadeh , E. Yusofi

We present a chaplygin gas Friedmann-Robertson-Walker quantum cosmological model. In this work the Schutz's variational formalism is applied with positive, negative, and zero constant spatial curvature. In this approach the notion of time…

General Relativity and Quantum Cosmology · Physics 2008-11-26 P. Pedram , S. Jalalzadeh , S. S. Gousheh

We investigate the evolution of non vacuum Friedmann-Lema\^itre-Robertson-Walker (FLRW) with any spatial curvature in the context of Gauss-Bonnet gravity. The analysis employs a new method which enables us to explore the phase space of any…

General Relativity and Quantum Cosmology · Physics 2017-09-13 Sante Carloni , José P. Mimoso

The consequence of energy conservation in the flat Friedmannn-Robertson-Walker (FRW) cosmology is a strictly positive accelerating expansion. A mechanism is proposed for this expansion due to the effect of the attractive (negative)…

General Relativity and Quantum Cosmology · Physics 2009-01-09 Steven Maxson
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