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Related papers: Constraints on the Generalized Chaplygin Gas Model…

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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

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

In this work, we investigate the cosmological dynamics of a spatially flat Friedmann--Lema\^itre--Robertson--Walker Universe in the framework of generalized \( \mathcal{F}(\mathcal{R},\Sigma,\mathcal{T}) \) gravity by incorporating…

General Relativity and Quantum Cosmology · Physics 2026-05-15 N. Myrzakulov , S. H. Shekh , Anirudh Pradhan , M. Zeyauddin

Gamma-Ray Bursts (GRB) are the most energetic events in the Universe, and provide a complementary probe of dark energy by allowing the measurement of cosmic expansion history that extends to redshifts greater than 6. Unlike Type Ia…

Astrophysics · Physics 2009-01-09 Yun Wang

Relations connecting gamma ray burst quantities can be used to constrain cosmographic parameters of the Hubble law at medium-high redshifts. We consider a sample of 27 gamma ray bursts to construct the luminosity distance to redshift…

Astrophysics · Physics 2010-01-09 S. Capozziello , L. Izzo

We use astrophysical data to shed light on fundamental physics by constraining parametrized theoretical cosmological and gravitational models. Gravitational parameters are those constants that parametrize possible departures from Einstein's…

Astrophysics · Physics 2008-08-18 Yi Mao

We present the results of analysis of constraints on cosmological parameters from cosmic microwave background (CMB) alone and in combination with galaxy cluster baryon fraction assuming inflation--generated adiabatic scalar fluctuations.…

Astrophysics · Physics 2009-11-06 M. Douspis , A. Blanchard , R. Sadat , J. G. Bartlett , M. Le Dour

It is well-known that allowing for spatial curvature affects constraints on cosmological parameters such as the dark energy equation of state parameters. Here we study the effect of curvature on constraints on parameters used to test…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 Jason Dossett , Mustapha Ishak

Reconstructing the expansion history of the Universe from type Ia supernovae data, we fit the growth rate measurements and put model-independent constraints on some key cosmological parameters, namely, $\Omega_\mathrm{m},\gamma$, and…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-10 Benjamin L'Huillier , Arman Shafieloo , Hyungjin Kim

In this paper we analyze the constraints on the property of dark energy from cosmological observations. Together with SNe Ia Gold sample, WMAP, SDSS and 2dFGRS data, we include 69 long Gamma-Ray Bursts (GRBs) data in our study and perform…

Astrophysics · Physics 2008-11-26 Hong Li , Meng Su , Zuhui Fan , Zigao Dai , Xinmin Zhang

In this paper, we propose extended Chaplygin gas equation of state for which it recovers barotropic fluid with quadratic equation of state. We use numerical method to investigate the behavior of some cosmological parameters such as scale…

General Relativity and Quantum Cosmology · Physics 2014-09-17 B. Pourhassan , E. O. Kahya

In this paper we investigate the role played by dark energy in the form of Generalized cosmic Chaplygin gas in an accelerating universe described by FRW cosmology. We have tried to describe the model from the theoretical point of view of a…

General Relativity and Quantum Cosmology · Physics 2013-07-11 Prabir Rudra

We present a maximum likelihood analysis of cosmological parameters from measurements of the aperture mass up to 35 arcmin, using simulated and real cosmic shear data. A four-dimensional parameter space is explored which examines the mean…

Astrophysics · Physics 2009-11-07 L. Van Waerbeke , Y. Mellier , R. Pello , U-L. Pen , H. J. McCracken , B. Jain

We use measurements of the growth of cosmic structure, as inferred from the observed evolution of the X-ray luminosity function (XLF) of galaxy clusters, to constrain departures from General Relativity (GR) on cosmological scales. We employ…

Astrophysics · Physics 2015-05-13 David Rapetti , Steven W. Allen , Adam Mantz , Harald Ebeling

There are a number of approaches to testing General Relativity (GR) on linear scales using parameterized frameworks for modifying cosmological perturbation theory. It is sometimes assumed that the details of any given parameterization are…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Joe Zuntz , Tessa Baker , Pedro Ferreira , Constantinos Skordis

We model the cosmological substratum by a viscous fluid that is supposed to provide a unified description of the dark sector and pressureless baryonic matter. In the homogeneous and isotropic background the \textit{total} energy density of…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 W Zimdahl , W S Hipólito-Ricaldi , H E S Velten

We develop a novel statistical strong lensing approach to probe the cosmological parameters by exploiting multiple redshift image systems behind galaxies or galaxy clusters. The method relies on free-form mass inversion of strong lenses and…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 M. Lubini , M. Sereno , J. Coles , Ph. Jetzer , P. Saha

This paper is devoted to the investigation of modified Chaplygin gas model in the context of solvable k-essence cosmologies. For this purpose, we construct equations of state parameter of this model for some particular values of the…

General Physics · Physics 2012-07-31 M. Sharif , K. R. Yesmakhanova , S. Rani , R. Myrzakulov

One approach in modern cosmology consists in supposing that dark matter and dark energy are different manifestations of a single `quartessential' fluid. Following such idea, this work presents a study of the evolution of perturbations of…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Sandro Silva e Costa , Maximiliano Ujevic , Alesandro Ferreira dos Santos

We review observational tests for the homogeneity of the Universe on large scales. Redshift and peculiar velocity surveys, radio sources, the X-Ray Background, the Lyman-$\alpha$ forest and the Cosmic Microwave Background are used to set…

Astrophysics · Physics 2007-05-23 Ofer Lahav