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Related papers: Modified Chaplygin Gas with Variable G and $\Lambd…

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The current work treats cosmological perturbation in a mixture of standard matter, Chaplygin gas as well as Gauss-bonnet fluids using a 1+3 covariant approach in the context of modified $f(G)$ gravity. We define the gradient variables to…

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

Cosmologies with running cosmological term (Lambda) and gravitational Newton's coupling (G) may naturally be expected if the evolution of the universe can ultimately be derived from the first principles of Quantum Field Theory or String…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 Javier Grande , Joan Sola , Julio C. Fabris , Ilya L. Shapiro

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 present work deals with scalar field cosmology in the framework of a quantum gravity modified Einstein-Hilbert Lagrangian with variable $G$ and $\Lambda$. Using Renormalization group, variable $G$ behaves as a minimally coupled filed…

General Relativity and Quantum Cosmology · Physics 2019-11-22 Santu Mondal , Sourav Dutta , Subenoy Chakraborty

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

We consider a mixture of varying Generalized Chaplyagin gas [1] interacting with a Tachyonic fluid in framework of GR. We suppose, that a Tachyonic fluid and Generalized Chaplyagin gas was separated somehow from Darkness of the Universe.…

General Physics · Physics 2013-02-06 Martiros Khurshudyan

In the framework of spatially averaged inhomogeneous cosmologies in classical general relativity, effective Einstein equations govern the dynamics of averaged scalar variables in a scale--dependent way. A particular cosmology may be…

General Relativity and Quantum Cosmology · Physics 2010-08-23 Xavier Roy , Thomas Buchert

We study the impact of a generalized Chaplygin gas as a candidate for dark energy on CMB anisotropies. The generalized Chaplygin gas is a fluid component with an exotic equation of state, $p = - A/\rho^\alpha$ (a polytropic gas with…

Astrophysics · Physics 2009-11-07 Daniela Carturan , Fabio Finelli

In this paper, we undertake a unified study of background dynamics and cosmological perturbations in the presence of the Chaplygin gas. This is done by first constraining the background cosmological parameters of different Chaplygin gas…

General Relativity and Quantum Cosmology · Physics 2023-10-12 Shambel Sahlu , Heba Sami , Renier Hough , Maye Elmardi , Anna-Mia Swart , Amare Abebe

In this work, we have considered interacting dynamical model taking variable modified Chaplygin gas which plays as dark energy coupled to cold dark matter in the flat FRW universe. Since the nature of dark energy and dark matter is still…

General Physics · Physics 2015-03-19 Jhumpa Bhadra , Ujjal Debnath

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

In this paper a possibility to accelerated the expansion of the large scale universe due to interacting varying Chaplygin gas of a specific form and a tachyonic matter is considered. A specific form of the potential and appropriate values…

General Physics · Physics 2017-08-16 Martiros Khurshudyan

We have presented a model in which the new generalized Chaplygin gas interacts with matter. We find that there exists a stable scaling solution at late times in the evolution of the universe. Moreover, the phantom crossing scenario is…

General Relativity and Quantum Cosmology · Physics 2010-04-30 Mubasher Jamil

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

Recently found accelarated expansion of our Universe is due to the presence of a new kind of matter called "$\Lambda$ - field" or quintessence. The limitations on its equation of state are found from the fact of its unclustering at all…

General Relativity and Quantum Cosmology · Physics 2009-11-07 D. Podolsky

We perform a phase space analysis of a generalized modified gravity theory with nonminimally coupling between geometry and matter. We apply the dynamical system approach to this generalized model and find that in the cosmological context,…

General Relativity and Quantum Cosmology · Physics 2016-05-17 Rui An , Xiaodong Xu , Bin Wang , Yungui Gong

In this paper we consider several phenomenological models of variable $\Lambda$. Model of a flat Universe with variable $\Lambda$ and $G$ is accepted. It is well known, that varying $G$ and $\Lambda$ gives rise to modified field equations…

General Relativity and Quantum Cosmology · Physics 2013-12-17 J. Sadeghi , M. Khurshudyan , A. Movsisyan , H. Farahani

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

The correspondence of the Gauss-Bonnet (GB) and its modification (MGB) models of dark energy with the standard and generalized Chaplygin gas-scalar field models (SCG and GCG) have been studied in a {\deg}at universe. The exact solution of…

General Relativity and Quantum Cosmology · Physics 2016-11-10 A. Khodam-Mohammadi , E. Karimkhani , A. Alaei