English
Related papers

Related papers: Viscous generalized Chaplygin gas

200 papers

Recent observations from type Ia Supernovae and from cosmic microwave background (CMB) anisotropies have revealed that most of the matter of the Universe interacts in a repulsive manner, composing the so-called dark energy constituent of…

General Relativity and Quantum Cosmology · Physics 2009-11-11 M. S. Santos , S. V. B. Gonçalves , J. C. Fabris , E. M. de Gouveia Dal Pino

We investigate observational constraints on the generalized Chaplygin gas (GCG) model including the gamma-ray bursts (GRBs) at high redshift obtained directly from the Union2 type Ia supernovae (SNe Ia) set. By using the Markov Chain Monte…

Cosmology and Nongalactic Astrophysics · Physics 2011-06-02 Nan Liang , Lixin Xu , Zong-Hong Zhu

A new diagnostic method, $Om$ is applied to generalized Chaplygin gas (GCG) model as the unification of dark matter and dark energy. On the basis of the recently observed data: the Union supernovae, the observational Hubble data, the SDSS…

Astrophysics · Physics 2010-11-02 Jianbo Lu , Lixin Xu

We present a holographic dark energy model of the universe considering modified generalized Chaplygin gas (GCG). The modified GCG behaves as an ordinary barotropic fluid in the early epoch when the universe was tiny but behaves subsequently…

General Relativity and Quantum Cosmology · Physics 2007-11-21 B. C. Paul , P. Thakur , A. Saha

We exploit the gauge-invariant formalism to analyse the perturbative behaviour of two cosmological models based on the generalized Chaplygin gas describing both dark matter and dark energy in the present Universe. In the first model we…

Astrophysics · Physics 2009-06-23 V. Gorini , A. Y. Kamenshchik , U. Moschella , O. F. Piattella , A. A. Starobinsky

We investigate the unification scenario provided by the generalised Chaplygin gas model (a perfect fluid characterized by an equation of state p = -A/\rho^{\alpha}). Our concerns lie with a possible tension existing between background…

Cosmology and Nongalactic Astrophysics · Physics 2014-07-18 Juliano Pereira Campos , Júlio César Fabris , Rafael Perez , Oliver F. Piattella , Hermano Velten

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

In the past few years, the Chaplygin gas (CG) has been considered as an appealing candidate for unifying dark matter and dark energy into a single substance. This picture had to face several problems when trying to fit its predictions with…

Astrophysics · Physics 2009-11-10 F. Perrotta , S. Matarrese , M. Torki

In this paper, we investigate cosmological models of the extended Chaplygin gas in a universe governed by Horava-Lifshitz gravity. The equation of state for an extended Chaplygin gas is a $(n+2)$-variable equation determined by $A_{n}$,…

General Relativity and Quantum Cosmology · Physics 2016-07-08 B. Pourhassan

In this paper we study FRW bulk viscous cosmology in presence of modified Chaplygin gas. We write modified Friedmann equations due to bulk viscosity and Chaplygin gas and obtain time-dependent energy density for the special case of flat…

General Physics · Physics 2016-12-02 H. Saadat , B. Pourhassan

The nature of the dark components (dark matter and dark energy) that dominate the current cosmic evolution is a completely open question at present. In reality, we do not even know if they really constitute two separated substances. In this…

Astrophysics · Physics 2009-11-10 Abha Dev , Deepak Jain , J. S. Alcaniz

We investigate observational constraints on the generalized Chaplygin gas (GCG) model as the unification of dark matter and dark energy from the latest observational data: the Union SNe Ia data, the observational Hubble data, the SDSS…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Jianbo Lu , Yuanxing Gui , Lixin Xu

We consider an anisotropic brane-world model with Bianchi type I and V geometry, without mirror symmetry or any form of junction conditions. The generalized Chaplygin gas, which interpolates between a high density relativistic era and a…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Malihe Heydari-Fard , Hamid R. Sepangi

We propose a scenario in which the dark components of the Universe are manifestations of a single bulk viscous fluid. Using dynamical system methods, a qualitative study of the homogeneous, isotropic background scenario is performed in…

Astrophysics · Physics 2008-12-18 R. Colistete , J. C. Fabris , J. Tossa , W. Zimdahl

We propose in this paper a new model for describing the unification of dark energy and dark matter. This new model is a further generalization of the generalized Chaplygin gas (GCG) model, thus dubbed new generalized Chaplygin gas (NGCG)…

Astrophysics · Physics 2009-11-10 Xin Zhang , Feng-Quan Wu , Jingfei Zhang

We have developed an action formulation for the Generalized Chaplygin Gas (GCG). The most general form for the nonrelativistic GCG action is derived consistent with the equation of state. We have also discussed a relativistic formulation…

General Relativity and Quantum Cosmology · Physics 2016-08-31 Rabin Banerjee , Subir Ghosh , Shailesh Kulkarni

In this letter we consider two different models of our present universe. We choose the models which are consisting different sets of two seperate fluids. The first one of each set tries to justify the late time acceleration and the second…

General Physics · Physics 2019-03-27 Promila Biswas , Ritabrata Biswas

The possibility that the present acceleration of the universe is driven by a kind of viscous fluid is exploited. At background level this model is similar to the generalized Chaplygin gas model (GCGM). But, at perturbative level, the…

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

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 exact solutions of the gravitational field equations in the generalized Randall-Sundrum model for an anisotropic brane with Bianchi type I geometry, with a generalized Chaplygin gas as matter source. The generalized Chaplygin…

General Relativity and Quantum Cosmology · Physics 2009-11-11 M. K. Mak , T. Harko