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We investigate the cosmological constraints on the Variable Chaplygin gas model from the latest observational data: SCP Union 2.1 compilation dataset of Type Ia supernovae (SNe Ia), Pantheon sample of SNe Ia, Platinum Sample of Gamma Ray…

Cosmology and Nongalactic Astrophysics · Physics 2023-07-11 Ashley Chraya , Yuvraj Muralichandran , Geetanjali Sethi

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 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 investigate observational constraints on the variable Chaplygin gas model from the gold sample of type Ia supernova data and the recent measurements of the X-ray gas mass fractions in galaxy clusters. Combining these databases, we obtain…

Astrophysics · Physics 2007-05-23 Zong-Kuan Guo , Yuan-Zhong Zhang

The type Ia supernovae observational data are used to estimate the parameters of a cosmological model with cold dark matter and the Chaplygin gas. The Chaplygin gas model depends essentially on four parameters: the Hubble constant, the…

Astrophysics · Physics 2009-12-30 R. Colistete , J. C. Fabris , S. V. B. Gonçalves , P. E. de Souza

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

In this paper, a modified Chaplygin gas model of unifying dark energy and dark matter with exotic equation of state $p=B\rho-\frac{A}{\rho^{\alpha}}$ which can also explain the recent accelerated expansion of the universe is investigated by…

Astrophysics · Physics 2008-11-26 Dao-jun Liu , Xin-zhou Li

We examine the variable Chaplygin gas (VCG) model with the aim of establishing tight constraints by using type-Ia supernovae, lookback time measurements, Baryon Acoustic Oscillations (BAO) and the Gamma Ray Bursts. We report the parameter…

Cosmology and Nongalactic Astrophysics · Physics 2019-05-31 Bhuvan Aggarwal , Geetanjali Sethi , Shruti Thakur

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

The generalized Chaplygin gas model with parameter space $\alpha>-1$ is studied in this paper. Some reasonable physical constraints are added to justify the use of the larger parameter space. The Type Ia supernova data and age data of some…

Astrophysics · Physics 2008-11-26 Yungui Gong

The supernova type Ia observational data are fitted using a model with cold dark matter and the Chaplygin gas. The Chaplygin gas, which is characterized by a negative pressure varying with the inverse of density, represents in this model…

Astrophysics · Physics 2007-05-23 J. C. Fabris , S. V. B. Goncalves , P. E. de Souza

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

A cosmological model with a new variant of Chaplygin gas obeying an equation of state(EoS), $P = A\rho - \frac{B}{\rho^{\alpha}}$ where $B= B_{0}a^{n}$ is investigated in the context of its thermodynamical behaviour. Here $B_{0}$ and $n$…

General Relativity and Quantum Cosmology · Physics 2017-02-07 D. Panigrahi , S. Chatterjee

The generalized Chaplygin gas model (GCGM) contains 5 free parameters, here, they are constrained through the type Ia supernovae data, i.e., the ``gold sample'' of 157 supernovae data. Negative and large positive values for $\alpha$ are…

Astrophysics · Physics 2009-12-30 R. Colistete , J. C. Fabris

In this Letter, a modified Chaplygin gas (MCG) model of unifying dark energy and dark matter with the exotic equation of state $p_{MCG}=B\rho_{MCG} -\frac A{\rho_{MCG}^\alpha}$ is constrained from recently observed data: the 182 Gold SNe…

Cosmology and Nongalactic Astrophysics · Physics 2010-05-07 Jianbo Lu , Lixin Xu , Jiechao Li , Baorong Chang , Yuanxing Gui , Hongya Liu

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

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

In a previous paper it was shown that any dark sector model can be mapped into a non-adiabatic fluid formed by two interacting components, one with zero pressure and the other with equation-of-state parameter $\omega = -1$. It was also…

Cosmology and Nongalactic Astrophysics · Physics 2014-10-27 S. Carneiro , C. Pigozzo

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

General Relativity and Quantum Cosmology · Physics 2014-11-17 M. C. Bento , O. Bertolami , A. A. Sen

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
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