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Related papers: Ruling out the Modified Chaplygin Gas Cosmologies

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We extend the equation of state of GCG (Generalized Chaplygin Gas) to $w<-1$ regime and show, from the point of view of dynamics, that the parameters of GCG should be in the range of $0<\alpha<1$. Also, dynamical analysis indicate that the…

Astrophysics · Physics 2009-11-10 Jian-gang Hao , Xin-zhou Li

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

A model of unification of dark matter and dark energy based on the modeling of the speed of sound as a function of the parameter of the equation of state is introduced. It is found that the model in which the speed of sound depends on the…

Cosmology and Nongalactic Astrophysics · Physics 2013-04-04 Neven Caplar , Hrvoje Stefancic

In this study, we investigate two dark energy models, MCJG and MCAG, in the context of $f(T)$ gravity within a non-flat FLRW Universe. Our analysis considers radiation, dark matter, and dark energy components. We compare the equation of…

General Relativity and Quantum Cosmology · Physics 2024-01-24 Himanshu Chaudhary , Ujjal Debnath , Tanusree Roy , Sayani Maity , G. Mustafa , Monika Arora

Observational manifestations of accelerated expansion of the universe, in particular, recent data for Type Ia supernovae, baryon acoustic oscillations, for the Hubble parameter $H(z)$ and cosmic microwave background constraints are…

General Relativity and Quantum Cosmology · Physics 2016-08-02 G. S. Sharov

We use the most recent Type-Ia Supernova data in order to study the dark energy - dark matter unification approach in the context of the Generalized Chaplygin Gas (GCG) model. Rather surprisingly, we find that data allow models with $\alpha…

Astrophysics · Physics 2009-09-11 O. Bertolami , A. A. Sen , S. Sen , P. T. Silva

In the present work, we have made an attempt to investigate the dark energy possibility from the thermodynamical point of view. For this purpose, we have studied thermodynamic stability of three popular dark energy models in the framework…

General Relativity and Quantum Cosmology · Physics 2021-01-18 Abdulla Al Mamon , Pritikana Bhandari , Subenoy Chakraborty

This article motivated by the recent articles and results of two authors. Recently, J. Sadeghi and H. Farahani presented a work [1], where they include viscosity and analyze general model, by this way they extended models considered by M.…

General Relativity and Quantum Cosmology · Physics 2016-01-05 J. Sadeghi , M. Khurshudyan , H. Farahani

This paper considers the spherically symmetric gravitational collapse in the background of Chaplygin gas as dark energy component. The dark energy is assumed to be generalized and modified Chaplygin gas. The exterior of the star is…

General Relativity and Quantum Cosmology · Physics 2023-03-14 Anjali Pandey , Rajesh Kumar , Sudhir Kumar Srivastava

In the frame of the scalar field model with non minimal kinetic coupling to gravity, we study the cosmological solutions of the Chaplygin gas model of dark energy. By appropriately restricting the potential, we found the scalar field, the…

High Energy Physics - Theory · Physics 2011-07-28 L. N. Granda , E. Torrente-Lujan , J. J. Fernandez-Melgarejo

In this paper we study the perturbations of a cosmic multi-fluid medium consisting of radiation, dust and a Chaplygin gas. To do so, we follow the 1 + 3 covariant formalism and derive the evolution equations of the fluctuations in the…

General Relativity and Quantum Cosmology · Physics 2020-10-27 Shambel Sahlu , Heba Sami , Anna-Mia Swart , Thato Tsabone , Maye Elmardi , Amare Abebe

The mass power spectrum for a Universe dominated by the Chaplygin gas is evaluated numerically from scales of the order of the Hubble horizon to 100 Mpc. The results are compared with a pure baryonic Universe and a cosmological constant…

Astrophysics · Physics 2016-08-16 J. C. Fabris , S. V. B. Gonçalves , P. E. de Souza

In this work we study different types of dark energy (DE) models in the framework of the cosmographic approach, with emphasis on the Running Vacuum models (RVMs). We assess their viability using different information criteria and compare…

Cosmology and Nongalactic Astrophysics · Physics 2021-11-25 Mehdi Rezaei , Joan Sola , Mohammad Malekjani

The Chaplygin gas has been proposed as a possible dark energy, dark matter candidate. As a working fluid in a Friedmann-Robertson-Walker universe, it exhibits early behavior reminiscent of dark matter, but at later times is more akin to a…

General Relativity and Quantum Cosmology · Physics 2011-03-07 T. C. Lipscombe

In this work the modified Chaplygin gas is related to a cosmological scalar field. Analytical results, more general than the solutions previously shown in the literature, are presented for the case when the curvature is absent, and one…

General Relativity and Quantum Cosmology · Physics 2008-03-03 Sandro Silva e Costa

We study the late-time evolution of the Universe where dark energy (DE) is presented by a barotropic fluid on top of cold dark matter (CDM). We also take into account the radiation content of the Universe. Here by the late stage of the…

General Relativity and Quantum Cosmology · Physics 2015-07-24 Ozgur Akarsu , Mariam Bouhmadi-López , Maxim Brilenkov , Ruslan Brilenkov , Maxim Eingorn , Alexander Zhuk

In this paper we consider a correspondence between the holographic dark energy density and Chaplygin gas energy density in FRW universe. Then we reconstruct the potential and the dynamics of the scalar field which describe the Chaplygin…

High Energy Physics - Theory · Physics 2010-10-27 M R Setare

The implications of considering interaction between Chaplygin gas and a barotropic fluid with constant equation of state have been explored. The unique feature of this work is that assuming an interaction $Q \propto H\rho_d$, analytic…

General Physics · Physics 2017-07-18 Subhajit Saha , Saumya Ghosh , Sunandan Gangopadhyay

The type Ia supernovae (SNe Ia) observational data are used to estimate the parameters of a cosmological model with cold dark matter and the generalized Chaplygin gas model (GCGM). The GCGM depends essentially on five parameters: the Hubble…

Astrophysics · Physics 2009-12-30 R. Colistete , J. C. Fabris , S. V. B. Goncalves

The present work is an attempt for emergent universe scenario with modified Chaplygin gas. The universe is chosen as spatially flat FRW space-time with modified Chaplygin gas as the only cosmic substratum. It is found that emergent scenario…

General Physics · Physics 2016-01-12 Sourav Dutta , Sudeshna Mukerji , Subenoy Chakraborty
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