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Related papers: Observational tests of non-adiabatic Chaplygin gas

200 papers

We explore the properties of dark energy from recent observational data, including the Gold Sne Ia, the baryonic acoustic oscillation peak from SDSS, the CMB shift parameter from WMAP3, the X-ray gas mass fraction in cluster and the Hubble…

Astrophysics · Physics 2008-11-26 Puxun Wu , Hongwei Yu

A unified model of dark energy and matter is presented using the modified variable Chaplygin gas for interacting dark energy in a non-flat universe. The two entities interact with each other non-gravitationally which involves a coupling…

Astrophysics · Physics 2008-12-18 Mubasher Jamil , Muneer A. Rashid

We investigate the observational viability of a class of cosmological models in which the vacuum energy density decays linearly with the Hubble parameter, resulting in a production of cold dark matter particles at late times. Similarly to…

Cosmology and Nongalactic Astrophysics · Physics 2011-09-01 C. Pigozzo , M. A. Dantas , S. Carneiro , J. S. Alcaniz

We constrain the parameters of the variable Chaplygin gas model, using the location of peaks of the CMBR spectrum and SNe Ia ``gold '' data set. Equation of state of the model is $P=-A(a)/\rho$, where $A(a)=A_0 a^{-n}$ is a positive…

Astrophysics · Physics 2008-11-26 Geetanjali Sethi , Sushil K. Singh , Pranav Kumar , Deepak Jain , Abha Dev

We investigate a model of interacting dark matter and dark energy given by a modified holographic Ricci cutoff in a spatially flat Friedmann-Robertson-Walker (FRW) space-time. We consider a nonlinear interaction consisting of a significant…

Cosmology and Nongalactic Astrophysics · Physics 2011-12-30 Luis P. Chimento , Martín G. Richarte

In this work the observational constraints on interaction coupling parameter between dynamical dark energy and cold dark matter were obtained using CMB, BAO and SN Ia data. The dark energy in considered models is dynamical and evolution of…

Cosmology and Nongalactic Astrophysics · Physics 2025-12-17 Roman Neomenko

We introduce an effective one-fluid description of the interacting dark sector in a spatially flat Friedmann-Robertson-Walker space-time and investigate the stability of the power-law solutions. We find the "source equation" for the total…

General Relativity and Quantum Cosmology · Physics 2015-06-04 Luis P. Chimento

We consider a non-linear interaction between the dark matter and dark energy components of the universe. In particular, within the FLRW geometry, where dark matter is described by a dust fluid and dark energy by an ideal gas with a constant…

Cosmology and Nongalactic Astrophysics · Physics 2025-09-24 Marcel van der Westhuizen , David Figueruelo , Rethabile Thubisi , Shambel Sahlu , Amare Abebe , Andronikos Paliathanasis

We have assumed the FRW model of the universe in Galileon gravity, which is filled with dark matter and Modified Chaplygin gas (MCG) type dark energy. We present the Hubble parameter in terms of some unknown parameters and observational…

General Physics · Physics 2015-06-19 Chayan Ranjit , Prabir Rudra , Ujjal Debnath

In this paper, we investigate a recent proposed model - so called the Tsallis holographic dark energy (THDE) model. In this case, we consider the non-gravitational and phenomenological interaction between dark sectors. We fit the free…

Cosmology and Nongalactic Astrophysics · Physics 2021-02-22 Ehsan Sadri

COBE-normalized flat (matter plus cosmological constant) and open Cold Dark Matter (CDM) models are tested by comparing their expected Hubble flow variations and the observed variations in a Type Ia supernova sample and a Tully Fisher…

Astrophysics · Physics 2009-10-30 Xiangdong Shi

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

We use the Markov Chain Monte Carlo method to investigate a global constraints on the modified Chaplygin gas (MCG) model as the unification of dark matter and dark energy from the latest observational data: the Union2 dataset of type…

Cosmology and Nongalactic Astrophysics · Physics 2011-05-12 Jianbo Lu , Lixin Xu , Yabo Wu , Molin Liu

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

We investigate the observational viability of a class of interacting dark energy (iDE) models in the light of the latest Cosmic Microwave Background (CMB), type Ia supernovae (SNe) and SH0ES Hubble parameter measurements. Our analysis…

Cosmology and Nongalactic Astrophysics · Physics 2021-08-10 Micol Benetti , Humberto Borges , Cassio Pigozzo , Saulo Carneiro , Jailson Alcaniz

We consider a generic cosmological model which allows for non-gravitational direct couplings between dark matter and dark energy. The distinguishing cosmological features of these couplings can be probed by current cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2018-01-17 Carsten van de Bruck , Jurgen Mifsud

The type Ia supernovae observational data is one of the most important in observational cosmology nowadays. Here we present the first public version of BETOCS (BayEsian Tools for Observational Cosmology using SNe Ia), which is a powerful…

Astrophysics · Physics 2007-05-23 R. Colistete , R. Giostri

We explore the possibility that the dark matter and dark energy are mimicked by a single fluid or by a single $k$-essence-like scalar field. The so called Chaplygin gas unified dark matter models can reproduce the observed matter power…

Cosmology and Nongalactic Astrophysics · Physics 2011-03-28 Yuko Urakawa , Tsutomu Kobayashi

The mixed cold-hot dark matter cosmological model (CHDM) with $\Omega_{tot}=1$ and a falling power-law initial spectrum of Gaussian adiabatic perturbations ($n>1$) is tested using recent obserbational data. It is shown that its fit to the…

Astrophysics · Physics 2009-10-22 Dmitri Pogosyan , Alexei Starobinsky

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