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We investigate the validity of the generalized second law (GSL) of gravitational thermodynamics in a non-flat FRW universe containing the interacting generalized Chaplygin gas with the baryonic matter. The dynamical apparent horizon is…

General Physics · Physics 2011-04-20 K. Karami , S. Ghaffari , M. M. Soltanzadeh

The so called Generalized Chaplygin Gas (GCG) with the equation of state $p = - \frac{A}{{\rho}^{\alpha}}$ was recently proposed as a candidate for dark energy in the Universe. In this paper we confront the GCG with SNIa data. Specifically…

Astrophysics · Physics 2009-11-10 Marek Biesiada , Wlodzimierz Godlowski , Marek Szydlowski

A unified treatment of mass varying dark matter coupled to cosmon-{\em like} dark energy is shown to result in {\em effective} generalized Chaplygin gas (GCG) scenarios. The mass varying mechanism is treated as a cosmon field inherent…

General Relativity and Quantum Cosmology · Physics 2014-11-20 Alex E. Bernardini

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 study the non-linear spherical "top hat" collapse for Chaplygin and viscous unified cosmologies. The term unified refers to models where dark energy and dark matter are replaced by one single component. For the generalized Chaplygin gas…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 Thiago R. P. Caramês , Júlio C. Fabris , Hermano E. S. Velten

This paper aims to study the use of future SNAP data together with the result of searches for strong gravitational lenses in future large quasar surveys to constrain the Generalized Chaplygin Gas (GCG) model. The GCG is considered as a…

Astrophysics · Physics 2009-11-07 P. T. Silva , O. Bertolami

In this paper, viscous generalized Chaplygin gas as a model of dark energy considered. We assume non-constant bulk viscous coefficient and study dark energy density. We consider several cases of density-dependent viscosities. We find that,…

General Relativity and Quantum Cosmology · Physics 2014-03-10 H. Saadat , B. Pourhassan

We study blackhole in the Modified Generalized Chaplygin Gas (MGCG) model, a modified gravity framework proposed to unify dark matter and dark energy. The resulting spacetime is asymptotically non-flat and feature two distinct horizons,…

General Relativity and Quantum Cosmology · Physics 2026-03-25 Sunil Singh Bohra

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 study the fate of density perturbations in an Universe dominate by the Chaplygin gas, which exhibit negative pressure. We show that it is possible to obtain the value for the density contrast observed in large scale structure of the…

General Relativity and Quantum Cosmology · Physics 2014-11-17 J. C. Fabris , S. V. B. Goncalves , P. E. de Souza

We use the Markov Chain Monte Carlo method to investigate a global constraints on the generalized Chaplygin gas (GCG) model as the unification of dark matter and dark energy from the latest observational data: the Constitution dataset of…

Cosmology and Nongalactic Astrophysics · Physics 2010-05-07 Lixin Xu , Jianbo Lu

In this paper, we study the thermodynamics and statistics of the galaxies clustering affected by the dynamical dark energy. We consider two important dark energy models based on time dependent equation of state to evaluate the gravitational…

General Physics · Physics 2020-08-27 Behnam Pourhassan , Sudhaker Upadhyay

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 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

We have investigated the thermodynamical properties of dark energy. Assuming that the dark energy temperature $T\sim a^{-n}$ and considering that the volume of the Universe enveloped by the apparent horizon relates to the temperature, we…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Yungui Gong , Bin Wang , Anzhong Wang

A new model for the universe filled with a generalized Chaplygin fluid is considered which unitarily describes as a single vacuum entity both a quintessence scalar field and a cosmological constant, so unifying the notion of dark energy.…

Astrophysics · Physics 2008-11-26 Pedro F. Gonzalez-Diaz

We revisit the paradigm of unified dark energy discussing in detail the averaging problem in this type of scenarios, highlighting the need for a full non-linear treatment. We also address the question of if and how models with one or…

Astrophysics · Physics 2009-11-13 P. P. Avelino , L. M. G. beça , C. J. A. P. Martins

On going good number of research works establish Modified Chaplygin Gas as one one of the most favoured candidates of Dark Energy. In our present work, new bound on the parameter space of associated model - parameter has been worked out…

General Physics · Physics 2010-06-09 Balendra Kr. Dev Choudhury , Julie Saikia

In this work, the collapsing process of a spherically symmetric star, made of dust cloud, is studied in Ho\v{r}ava Lifshitz gravity in the background of Chaplygin gas dark energy. Two different classes of Chaplygin gas, namely, New variable…

General Physics · Physics 2014-05-30 Prabir Rudra , Ujjal Debnath

We study the effect of shear and rotation on results previously obtained dealing with the application of the spherical collapse model (SCM) to generalized Chaplygin gas (gCg) dominated universes. The system is composed of baryons and gCg…

Cosmology and Nongalactic Astrophysics · Physics 2013-03-18 A. Del Popolo , F. Pace , S. P. Maydanyuk , J. A. S. Lima , J. F. Jesus