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Related papers: Confronting the Chaplygin gas with data: backgroun…

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We study the spherical top-hat collapse in Einstein gravity and loop quantum cosmology by taking the non-linear evolution of viscous modified variable chaplygin gas and viscous generalized cosmic chaplygin gas. We calculate the equation of…

General Relativity and Quantum Cosmology · Physics 2016-11-09 Abdul Jawad , Ayesha Iqbal

The generalized Chaplygin gas model is characterized by the equation of state $p = - \frac{A}{\rho^\alpha}$. It is generally stated that the case $\alpha = 0$ is equivalent to a model with cosmological constant and dust ($\Lambda CDM$). In…

Astrophysics · Physics 2009-11-10 J. C. Fabris , S. V. B. Gonçalves , R. de Sá Ribeiro

We have explored the possibility of the co-existence of two forms of dark energy in the form of an alternative Generalized Chaplygin Gas (GCG) along with a scalar field of field theoretic or extra dimensional origin in the background of a…

General Relativity and Quantum Cosmology · Physics 2026-01-28 Mahasweta Biswas , Rikpratik Sengupta , Ujjal Debnath

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 explore the implications of type Ia supernovae (SNIa) observations on flat cosmological models whose matter content is an exotic fluid with equation of state, p=-M^(4(a+1))/rho^a. In this scenario, a single fluid component may drive the…

Astrophysics · Physics 2016-08-30 Martin Makler , Sergio Quinet de Oliveira , Ioav Waga

We explicitly demonstrate that, contrary to recent claims, the dynamics of a generalized Chaplygin gas model with an equation of state $p=-C$ (where $C$ is a positive constant) is equivalent to that of a standard $\Lambda$CDM model to first…

Astrophysics · Physics 2009-11-10 P. P. Avelino , L. M. G. Beca , J. P. M. de Carvalho , C. J. A. P. Martins

With considerations of the recently released WMAP year three and supernova legacy survey (SNLS) data set analysis that favors models similar to the $% \Lambda CDM$ model by possibly mild fluctuations around the vacuum energy or the…

Astrophysics · Physics 2007-05-23 Xin He Meng , Ming Guang Hu , Jie Ren

In this letter we consider two different models of our present universe. We choose the models which are consisting different sets of two seperate fluids. The first one of each set tries to justify the late time acceleration and the second…

General Physics · Physics 2019-03-27 Promila Biswas , Ritabrata Biswas

We study the effects of vacuum energy perturbations on the evolution of the dark matter growth rate in a decomposed Chaplygin gas model with interacting dark matter and vacuum energy. We consider two different cases: (i) geodesic dark…

Cosmology and Nongalactic Astrophysics · Physics 2018-11-12 Humberto A. Borges , Patrícia Hepp

We study the dependence of the location of the Cosmic Microwave Background Radiation (CMBR) peaks on the parameters of the generalized Chaplygin gas model, whose equation of state is given by $p = - A/\rho^{\alpha}$, where $A$ is a positive…

Astrophysics · Physics 2009-11-07 M. C. Bento , O. Bertolami , A. A. Sen

We study the implications on both background and perturbation evolution of introducing a Chaplygin gas component in the universe's ingredients. We perform likelihood analyses using wide-ranging, SN1a, CMB and large scale structure…

Astrophysics · Physics 2010-04-06 Rachel Bean , Olivier Doré

We consider a universe filled by a modified generalized Chaplygin gas together with a pressureless dark matter component. We get a thermodynamical interpretation for the modified generalized Chaplygin gas confined to the apparent horizon of…

General Relativity and Quantum Cosmology · Physics 2016-05-18 H. Ebadi , H. Moradpour

We model the cosmic medium as the mixture of a generalized Chaplygin gas and a pressureless matter component. Within a neo-Newtonian approach we compute the matter power spectrum. The 2dFGRS data are used to discriminate between unified…

Astrophysics · Physics 2015-05-13 J. C. Fabris , S. V. B. Goncalves , H. E. S. Velten , W. Zimdahl

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

Even though many scalar field models of dark energy have been considered in the literature, there is another interesting class of dark energy models involving a fluid known as a Chaplygin gas. In addition to describing the dark energy, both…

General Relativity and Quantum Cosmology · Physics 2021-06-14 Amin Rezaei Akbarieh , Mohammad Ahmadi , Yousef Izadi , Shahabeddin M. Aslmarand , Warner A. Miller

In this work we study in detail a phenomenological generalization of the Chaplygin cosmological model, which we call as \textit{umami} Chaplygin model. We consider three different cosmological background scenarios in which our fluid can…

Cosmology and Nongalactic Astrophysics · Physics 2019-03-04 Ruth Lazkoz , María Ortiz-Baños , Vincenzo Salzano

The modified Chaplygin gas (MCG) cosmological model is derived by using the geometrothermodynamics (GTD) formalism. We show that the MCG corresponds to a system with internal thermodynamic interaction and describes the current accelerated…

General Relativity and Quantum Cosmology · Physics 2019-01-15 Hachemi B. Benaoum , Hernando Quevedo

The goal of this paper is to discuss phase space analysis of some interacting Chaplygin gas models in General Relativity. Chaplygin gas is one of the fluids actively considered in modern cosmology due to the fact that it is a joint model of…

General Relativity and Quantum Cosmology · Physics 2015-09-09 M. Khurshudyan , R. Myrzakulov

In this work we explore an alternative phenomenological model to Chaplygin gas proposed by H. Hova et. al., consisting on a modification of a perfect fluid, to explain the dynamics of dark matter and dark energy at cosmological scales…

Cosmology and Nongalactic Astrophysics · Physics 2019-01-30 A. Hernandez-Almada , Juan Magana , Miguel A. Garcia-Aspeitia , V. Motta

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
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