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Related papers: Cosmology with a Variable Chaplygin Gas

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We use the Type Ia Supernova gold sample to constrain the parameters of dark energy models namely the Cardassian, Dvali-Turner (DT) and generalized Chaplygin gas (GCG) models. In our best fit analysis for these dark energy proposals we…

Astrophysics · Physics 2015-06-24 M. C. Bento , O. Bertolami , N. M. C. Santos , A. A. Sen

A particular generalization of the Chaplygin inflationary model, using the formalism of Hamilton-Jacobi and elliptic functions, results in a more general non-linear Chaplygin-type equation of state (Chaplygin-Jacobi model). We investigate…

General Relativity and Quantum Cosmology · Physics 2025-03-11 J. A. S. Fortunato , W. S. Hipolito-Ricaldi , N. Videla , J. R. Villanueva

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

Explanations to the accelerated expansion of the Universe are usually sought either in modifications of Einstein gravity or in new forms of energy density. An example of modified gravity is the braneworld Dvali-Gabadadze-Porrati (DGP) model…

Astrophysics · Physics 2008-04-22 Matts Roos

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 review the difficulties of the generalized Chaplygin gas model to fit observational data, due to the tension between background and perturbative tests. We argue that such issues may be circumvented by means of a self-interacting scalar…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 J. C. Fabris , O. F. Piattella , D. C. Rodrigues , C. E. M. Batista , M. H. Daouda

Recently, a model of modified gravity plus single scalar field model was proposed, in which the scalar couples both to the standard Riemannian volume form given by the square root of the determinant of the Riemannian metric, as well as to…

General Relativity and Quantum Cosmology · Physics 2016-12-09 Denitsa Staicova , Michail Stoilov

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…

We study the general properties of a spherically symmetric body described through the generalized Chaplygin equation of state. We conclude that such object, dubbed generalized Chaplygin dark star, should exist within the context of the…

Astrophysics · Physics 2009-11-13 O. Bertolami , J. Paramos

Motivated by some previous works of Rudra et al we set to explore the background dynamics when dark energy in the form of New Variable Modified Chaplygin gas is coupled to dark matter with a suitable interaction in the universe described by…

General Physics · Physics 2015-06-15 Prabir Rudra , Chayan Ranjit , Sujata Kundu

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

Accelerating Chaplygin gas combined with the decelerating braneworld Dvali-Gabadadze-Porrati (DGP) model can produce an overall accelerated expansion of the order of magnitude seen. Both models have similar asymptotic properties at early…

Astrophysics · Physics 2008-12-18 Matts Roos

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

We use different combinations of data samples to investigate the new generalized Chaplygin gas (NGCG) model in the context of dark energy (DE) cosmology. Using the available cosmological data, we put constraints on the the free parameters…

Cosmology and Nongalactic Astrophysics · Physics 2022-01-19 Fataneh Salahedin , Reza Pazhouhesh , Mohammad Malekjani

The cosmic coincidence problem is a serious challenge to dark energy model. We suggest a quantitative criteria for judging the severity of the coincidence problem. Applying this criteria to three different interacting models, including the…

Cosmology and Nongalactic Astrophysics · Physics 2009-07-24 Hongsheng Zhang , Heng Yu , Zong-Hong Zhu , Yungui Gong

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

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

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

We show that a generalised phantom Chaplygin gas can present a future singularity in a finite future cosmic time. Unlike the big rip singularity, this singularity happens for a finite scale factor, but like the big rip singularity, it would…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Mariam Bouhmadi-Lopez , Pedro F. Gonzalez-Diaz , Prado Martin-Moruno

In cosmology based on general relativity, the universe is modeled as a fluid. The transition from the Einstein field equation to its large-scale (cosmological) version is thus analogous to the transition, for a system consisting of a large…

General Physics · Physics 2018-10-18 Gregory Ryskin
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