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Related papers: Challenges to the Generalized Chaplygin Gas Cosmol…

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Unified dark matter models are appealing in that they describe the dark sector in terms of a single component. They however face problems when attempting to account for structure formation: in the linear regime, density fluctuations can…

Cosmology and Nongalactic Astrophysics · Physics 2015-09-16 Amr El-Zant

We use the latest data to investigate observational constraints on the new generalized Chaplygin gas (NGCG) model. Using the Markov Chain Monte Carlo (MCMC) method, we constrain the NGCG model with the type Ia supernovae (SNe Ia) from…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 Kai Liao , Yu Pan , Zong-Hong Zhu

Neutrinos coupled to an underlying scalar field in the scenario for unification of mass varying dark matter and cosmon-{\em like} dark energy is examined. In the presence of a tiny component of mass varying neutrinos, the conditions for the…

Cosmology and Nongalactic Astrophysics · Physics 2011-02-15 Alex E. Bernardini

The generalized Chaplygin gas provides an interesting candidate for the present accelerated expansion of the universe. We explore a geometrical explanation for the generalized Chaplygin gas within the context of brane world theories where…

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

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

The generalized Chaplygin gas is usually defined as a barotropic perfect fluid with an equation of state $p=-A \rho^{-\alpha}$, where $\rho$ and $p$ are the proper energy density and pressure, respectively, and $A$ and $\alpha$ are positive…

General Relativity and Quantum Cosmology · Physics 2018-08-22 V. M. C. Ferreira , P. P. Avelino

A new model describing the dark sector of the universe is established. The model involves Bose-Einstein condensate (BEC) as dark energy (DE) and an excited state above it as dark matter (DM). The condensate is assumed to have a negative…

General Relativity and Quantum Cosmology · Physics 2011-05-24 V. A. Popov

The generalized Chaplygin gas, which interpolates between a high density relativistic era and a non-relativistic matter phase, is a popular dark energy candidate. We consider a generalization of the Chaplygin gas model, by assuming the…

General Relativity and Quantum Cosmology · Physics 2008-11-26 C. S. J. Pun , L. Á. Gergely , M. K. Mak , Z. Kovács , G. M. Szabó , T. Harko

Cosmologies with a Chaplygin gas have recently been explored with the objective of explaining the transition from a dust dominated epoch towards an accelerating expansion stage. We consider the hypothesis that the transition to the…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Mariam Bouhmadi-Lopez , Paulo Vargas Moniz

In this paper, we investigate cosmological consequences of a scenario for recently reported accelerated expansion of the Universe, in which the generalized Chaplygin gas (GCG) along with the baryonic matter are responsible for this observed…

General Relativity and Quantum Cosmology · Physics 2017-05-24 Hamid Shabani

This paper is devoted to the investigation of modified Chaplygin gas model in the context of solvable k-essence cosmologies. For this purpose, we construct equations of state parameter of this model for some particular values of the…

General Physics · Physics 2012-07-31 M. Sharif , K. R. Yesmakhanova , S. Rani , R. Myrzakulov

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

The cosmological observations suggest that the presently accelerating universe should be filled by an exotic form of matter, violating the strong energy condition, of unknown nature and origin. We propose the viscous dark matter of a source…

General Relativity and Quantum Cosmology · Physics 2020-08-05 Marek Szydlowski , Adam Krawiec

We consider a new generalized Chaplygin gas model that includes the original Chaplygin gas model as a special case. In such a model the generalized Chaplygin gas evolves as from dust to quiessence or phantom. We show that the background…

Astrophysics · Physics 2008-11-26 Zong-Kuan Guo , Yuan-Zhong Zhang

In the paper, we have presented a higher-dimensional cosmological model with a generalized Chaplygin-type gas to explain the recent acceleration of the universe. Dimensional reduction is feasible in this model, and our solutions are…

General Relativity and Quantum Cosmology · Physics 2025-07-01 D. Panigrahi , B. C. Paul , S. Chatterjee

Motivated by recent developments in particle physics and cosmology, there has been growing interest in an unified description of dark matter and dark energy scenarios. In this paper we explore observational constraints from age estimates of…

Astrophysics · Physics 2011-06-21 J. S. Alcaniz , Deepak Jain , Abha Dev

We discuss the prospects of using Gamma Ray Bursts (GRBs) as high-redshift distance estimators, and consider their use in the study of two dark energy models, the Generalized Chaplygin Gas (GCG), a model for the unification of dark energy…

Astrophysics · Physics 2007-05-23 O. Bertolami , P. T. Silva

The Universe is modeled as consisting of pressureless baryonic matter and a bulk viscous fluid which is supposed to represent a unified description of the dark sector. In the homogeneous and isotropic background the \textit{total} energy…

Cosmology and Nongalactic Astrophysics · Physics 2011-11-22 W. Zimdahl , H. E. S. Velten , W. S. Hipólito-Ricaldi

We study Modified Chaplygin Gas (MCG) as a candidate for dark energy and predict the values of parameters of the gas for a physically viable cosmological model. The equation of state of MCG ($p=B \rho - \frac {A}{\rho^\alpha} $) involves…

Cosmology and Nongalactic Astrophysics · Physics 2013-02-27 P. Thakur , S. Ghose , B. C. Paul

Viscous GCG(generalized Chaplygin gas) cosmology is discussed, assuming that there is bulk viscosity in the barotropic fluid and GCG. The dynamical analysis indicates that the phase…

Astrophysics · Physics 2009-11-11 Xiang-hua Zhai , You-dong Xu , Xin-zhou Li
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