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The generalized Chaplygin gas (GCG) model allows for an unified description of the cosmologically recent accelerated expansion of the Universe and of the evolution of energy density perturbations. This dark energy - dark matter unification…

Astrophysics · Physics 2007-05-23 O. Bertolami

The generalized Chaplygin gas (GCG) model explains the recent accelerated expansion of the Universe via an exotic background fluid whose equation of state is given by p=-A/\rho^\alpha, where A is a positive constant and 0<\alpha\le 1. The…

Astrophysics · Physics 2015-06-24 M. C. Bento , O. Bertolami , A. A. Sen

The generalized Chaplygin gas is characterized by the equation of state p = - A/rho^alpha, with alpha > -1 and w > -1. We generalize this model to allow for the cases where alpha < -1 or w < -1. This generalization leads to three new…

Astrophysics · Physics 2013-05-29 A. A. Sen , Robert J. Scherrer

The generalized Chaplygin gas (GCG) model is the prototype of a unified model of dark energy (DE) and dark matter (DM). It is characterized by equation-of-state (EoS) parameters $A$ and $\alpha$. We use a statistical analysis of the 2dFGRS…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-22 J. C. Fabris , H. E. S. Velten , W. Zimdahl

The generalized Chaplygin gas (GCG) model allows for an unified description of the recent accelerated expansion of the Universe and the evolution of energy density perturbations. This dark energy - dark matter unification is achieved…

General Relativity and Quantum Cosmology · Physics 2014-11-17 M. C. Bento , O. Bertolami , A. A. Sen

Recently developed Generalized Cosmic Chaplygin gas (GCCG) is studied as an unified model of dark matter and dark energy. To explain the recent accelerating phase, the Universe is assumed to have a mixture of radiation and GCCG. The mixture…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Writambhara Chakraborty , Ujjal Debnath , Subenoy Chakraborty

In this paper, we reexamine the generalized Chaplygin gas (GCG) cosmology with the sign-changeable interaction. The dynamical analysis show that there exists de-Sitter attractors in this model, which means that the late-time behaviors of…

General Relativity and Quantum Cosmology · Physics 2015-10-13 Ping Xi , Ping Li

We apply methods of dynamical systems to study the behaviour of universe dominated by the generalized Chaplygin gas. We reduce the dynamics to a 2-dimensional Hamiltonian system and study its behaviour for various ranges of parameters. The…

Astrophysics · Physics 2009-11-10 Marek Szydlowski , Wojciech Czaja

In this paper, we revisit generalized Chaplygin gas (GCG) model as a unified dark matter and dark energy model. The energy density of GCG model is given as $\rho_{GCG}/\rho_{GCG0}=[B_{s}+(1-B_{s})a^{-3(1+\alpha)}]^{1/(1+\alpha)}$, where…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Lixin Xu , Jianbo Lu , Yuting Wang

The generalized Chaplygin gas (GCG) model in spatially flat universe is investigated. The cosmological consequences led by GCG model including the evolution of EoS parameter, deceleration parameter and dimensionless Hubble parameter are…

General Relativity and Quantum Cosmology · Physics 2011-06-10 M. Malekjani , A. Khodam-Mohammadi , N. Nazari-Pooya

We study the Generalized Chaplygin gas model (GCGM) using Gamma-ray bursts as cosmological probes. In order to avoid the so-called circularity problem we use cosmology-independent data set and Bayesian statistics to impose constraints on…

Cosmology and Nongalactic Astrophysics · Physics 2011-08-19 R. C. Freitas , S. V. B. Gonçalves , H. E. S. Velten

We study the main cosmological properties of the Generalized Chaplygin Gas (GCG) dark energy model at the background and perturbation levels. By using the latest cosmological data in both the background and perturbation levels, we implement…

Cosmology and Nongalactic Astrophysics · Physics 2022-03-14 S. F. Salahedin , M. Malekjani , K. Y. Roobiat , R. Pazhouhesh

Yes, but only for a parameter value that makes it almost coincide with the standard model. We reconsider the cosmological dynamics of a generalized Chaplygin gas (gCg) which is split into a cold dark matter (CDM) part and a dark energy (DE)…

Cosmology and Nongalactic Astrophysics · Physics 2017-02-03 R. F. vom Marttens , L. Casarini , W. Zimdahl , W. S. Hipólito-Ricaldi , D. F. Mota

The standard model of cosmology is investigated using time dependent cosmological constant $\Lambda$ and Newton's gravitational constant $G$. The total energy content is described by the modified Chaplygin gas equation of state. It is found…

General Relativity and Quantum Cosmology · Physics 2009-03-12 Mubasher Jamil , Farook Rahaman , Mehedi Kalam

The generalized Chaplygin gas (GCG), which has an unusual perfect fluid equation of state, is another promising candidate for dark energy. We investigate the GCG scenario coupled with a baryonic matter in a newly suggested $f(Q,T)$ gravity,…

General Relativity and Quantum Cosmology · Physics 2022-06-24 Gaurav N. Gadbail , Simran Arora , P. K. Sahoo

We have explored the possibility of the co-existence of two forms of dark energy in the form of an alternative Generalized Chaplygin Gas (GCG) along with a scalar field of field theoretic or extra dimensional origin in the background of a…

General Relativity and Quantum Cosmology · Physics 2026-01-28 Mahasweta Biswas , Rikpratik Sengupta , Ujjal Debnath

The viability of the variable generalised Chaplygin gas (VGCG) model is analysed from the standpoint of its thermodynamical stability criteria with the help of an equation of state, $P = - \frac{B}{\rho^{\alpha}}$, where $B =…

General Relativity and Quantum Cosmology · Physics 2017-02-17 D. Panigrahi , S. Chatterjee

We use the hybrid model of bulk viscosity and generalized chaplygin gas (GCG), named the viscous generalized chaplygin gas (VGCG) model, which is thought to be an alternate dark fluid of the universe. We explore the dynamics of the VGCG…

General Relativity and Quantum Cosmology · Physics 2023-03-13 Gaurav N. Gadbail , Simran Arora , P. K. Sahoo

The generalized Chaplygin gas model is characterized by the equation of state $p = - \frac{A}{\rho^\alpha}$. It is generally stated that the case $\alpha = 0$ is equivalent to a model with cosmological constant and dust ($\Lambda CDM$). In…

Astrophysics · Physics 2009-11-10 J. C. Fabris , S. V. B. Gonçalves , R. de Sá Ribeiro

We study the cosmological scenario arising from the dynamics of a generalized Chaplygin gas. The equation of state of the system is given in terms of the energy density, $\rho$, and pressure, $p$, by the relationship $p = -…

Astrophysics · Physics 2007-05-23 M. C. Bento , O. Bertolami , A. A. Sen
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