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Related papers: Observational tests of non-adiabatic Chaplygin gas

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We consider unified dark sector models in which the fluid can collapse and cluster into halos, allowing for hierarchical structure formation to proceed as in standard cosmology. We show that both background evolution and linear…

Cosmology and Nongalactic Astrophysics · Physics 2025-02-05 Mahmoud Hashim , Amr El-Zant

The generalized Chaplygin gas cosmology provides a prime example for the class of unified dark matter models, which substitute the two dark components of the standard cosmological LCDM concordance model by a single dark component. The…

Cosmology and Nongalactic Astrophysics · Physics 2017-11-28 Ralf Aurich , Sven Lustig

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 extend our previous analysis and consider the interacting holographic Ricci dark energy (IRDE) model in non-flat universe. We study astrophysical constraints on this model using the recent observations including the type Ia supernovae…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-23 Masashi Suwa , Koji Kobayashi , Hisashi Oshima

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

The generalized Chaplygin gas (GCG) model allows for an unified description of the cosmologically recent accelerated expansion of the Universe and of the evolution of energy density perturbations. This dark energy - dark matter unification…

Astrophysics · Physics 2007-05-23 O. Bertolami

The possibility of unifying dark-matter and dark-energy has recently attracted considerable interest. In this so called quartessence scenario, a single component is responsible for both the clustering of matter and the accelerated expansion…

Astrophysics · Physics 2010-11-05 R. R. R. Reis , M. Makler , I. Waga

We study the nonlinear regime of Unified Dark Energy models, using Generalized Chaplygin Gas cosmologies as a representative example, and introduce a new parameter characterizing the level of small scale clustering in these scenarios. We…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-19 P. P. Avelino , K. Bolejko , G. F. Lewis

In this paper, we revisit generalized Chaplygin gas (GCG) model as a unified dark matter and dark energy model. The energy density of GCG model is given as $\rho_{GCG}/\rho_{GCG0}=[B_{s}+(1-B_{s})a^{-3(1+\alpha)}]^{1/(1+\alpha)}$, where…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Lixin Xu , Jianbo Lu , Yuting Wang

We study the main cosmological properties of the Generalized Chaplygin Gas (GCG) dark energy model at the background and perturbation levels. By using the latest cosmological data in both the background and perturbation levels, we implement…

Cosmology and Nongalactic Astrophysics · Physics 2022-03-14 S. F. Salahedin , M. Malekjani , K. Y. Roobiat , R. Pazhouhesh

In this paper, we discuss a model-independent way to obtain the present dark matter density parameter ($\Omega_{\rm{c,0}}$) by combining gas mass fraction measurements in galaxy clusters ($f_{gas}$), type Ia supernovae (SNe Ia) observations…

Cosmology and Nongalactic Astrophysics · Physics 2019-12-04 R. F. L. Holanda , R. S. Gonçalves , J. E. Gonzales , J. S. Alcaniz

Spherically symmetric dark energy structures are investigated in the framework of a generalized Chaplygin gas (GCG), which has an equation of state of the form $P = - A/\rho^{\alpha}} $. We also study these in a modified GCG equation of…

General Relativity and Quantum Cosmology · Physics 2007-06-07 Abiy G. Tekola

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 investigate cosmological constraints on the Variable Chaplygin gas model parameters with latest observational data of the Fast Radio Bursts and compare the results with previous constraints obtained using SNe Ia (Pantheon+SHOES), Gamma…

Cosmology and Nongalactic Astrophysics · Physics 2024-04-25 Geetanjali Sethi , Udish Sharma , Nadia Makhijani

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

In this paper, we have considered new modified Chaplygin gas (NMCG) model which interpolates between radiation at early stage and $\Lambda$CDM at late stage. This model is regarded as a unification of dark energy and dark matter (with…

General Relativity and Quantum Cosmology · Physics 2008-12-18 Surajit Chattopadhyay , Ujjal Debnath

We investigate the observational constraints on an interacting vacuum energy scenario with two different neutrino schemes (with and without a sterile neutrino) using the most recent data from CMB temperature and polarization anisotropy,…

Cosmology and Nongalactic Astrophysics · Physics 2017-11-15 Suresh Kumar , Rafael C. Nunes

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 hypothesis that dark matter and dark energy are unified through the Chaplygin gas is reexamined. Using a generalization of the spherical model which incorporates effects of the acoustic horizon we show that an initially perturbative…

Astrophysics · Physics 2007-05-23 Neven Bilic , Robert J. Lindebaum , Gary B. Tupper , Raoul D. Viollier

In previous papers, a cosmological model with constant-rate particle creation and vacuum term decaying linearly with the Hubble parameter was shown to lead to a good concordance when tested against precise observations: the position of the…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-09 Hermano Velten , Ariadna Montiel , Saulo Carneiro
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