English
Related papers

Related papers: CMBR Constraint on a Modified Chaplygin Gas Model

200 papers

We compare the WMAP temperature power spectrum and SNIa data to models with a generalized Chaplygin gas as dark energy. The generalized Chaplygin gas is a component with an exotic equation of state, p_X=-A/\rho^\alpha_X (a polytropic gas…

Astrophysics · Physics 2009-11-07 L. Amendola , F. Finelli , C. Burigana , D. Carturan

Assuming the flat FRW universe in Einstein's gravity filled with New Variable Modified Chaplygin gas (NVMCG) dark energy and dark matter having negligible pressure. In this research work we analyze the viability on the basis of recent…

General Physics · Physics 2012-11-13 Jhumpa Bhadra , Ujjal Debnath

In this work, we have considered the flat FRW model of the universe in $(n+2)$-dimensions filled with the dark matter (perfect fluid with negligible pressure) and the modified Chaplygin gas (MCG) type dark energy. We present the Hubble…

General Physics · Physics 2015-09-09 Chayan Ranjit , Shuvendu Chakraborty , Ujjal Debnath

We show that the observed rotation curves of spiral galaxies constrain the sound speed of the dark matter to be $c_s < 10^{-4} c$, where $c$ is the speed of light in vacuum. Using the Modified Chaplygin Gas as a representative example of a…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-06 P. P. Avelino , V. M. C. Ferreira

FRW universe in RS II braneworld model filled with a combination of dark matter and dark energy in the form of modified Chaplygin gas (MCG) is considered. It is known that the equation of state (EoS) for MCG is a three-variable equation…

General Physics · Physics 2015-06-15 Chayan Ranjit , Prabir Rudra , Sujata Kundu

Unified Dark Matter models describe Dark Matter and Dark Energy as a single entity which is, in the simplest case, embodied in a perfect barotropic fluid. It is a well-established fact that small adiabatic perturbations of Unified Dark…

Cosmology and Nongalactic Astrophysics · Physics 2010-05-28 Oliver F. Piattella

We study a generalized version of Chaplygin gas as unified model of dark matter and dark energy. Using realistic theoretical models and the currently available observational data from the age of the universe, the expansion history based on…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-15 Chan-Gyung Park , Jai-chan Hwang , Jaehong Park , Hyerim Noh

We have considered the FRW universe in loop quantum cosmology (LQC) model filled with the dark matter (perfect fluid with negligible pressure) and the modified Chaplygin gas (MCG) type dark energy. We present the Hubble parameter in terms…

General Physics · Physics 2015-06-05 Shuvendu Chakraborty , Ujjal Debnath , Chayan Ranjit

The Modified Chaplygin Gas (MCG) model is revisited to examine its ability to describe the full cosmic evolution within a single framework. Because the field equations are highly nonlinear, no closed analytical solution for the scale factor…

General Relativity and Quantum Cosmology · Physics 2025-12-23 D. Panigrahi , S. Chatterjee , B. C. Paul

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 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 study the cosmological scenario arising from the dynamics of a generalized Chaplygin gas. The equation of state of the system is given in terms of the energy density, $\rho$, and pressure, $p$, by the relationship $p = -…

Astrophysics · Physics 2007-05-23 M. C. Bento , O. Bertolami , A. A. Sen

We investigate the evolution of a FRW model fuelled by a modified Chaplygin gas with an equation of state $p = A\rho -\frac{B}{\rho^\alpha}$. An attempt is made here to constrain the free parameters of MCG model through the wellknown…

General Relativity and Quantum Cosmology · Physics 2015-10-23 D. Panigrahi , B. C. Paul , S. Chatterjee

The generalized Chaplygin gas (GCG) model is the prototype of a unified model of dark energy (DE) and dark matter (DM). It is characterized by equation-of-state (EoS) parameters $A$ and $\alpha$. We use a statistical analysis of the 2dFGRS…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-22 J. C. Fabris , H. E. S. Velten , W. Zimdahl

We propose in this paper a new model for describing the unification of dark energy and dark matter. This new model is a further generalization of the generalized Chaplygin gas (GCG) model, thus dubbed new generalized Chaplygin gas (NGCG)…

Astrophysics · Physics 2009-11-10 Xin Zhang , Feng-Quan Wu , Jingfei Zhang

We study the impact of a generalized Chaplygin gas as a candidate for dark energy on CMB anisotropies. The generalized Chaplygin gas is a fluid component with an exotic equation of state, $p = - A/\rho^\alpha$ (a polytropic gas with…

Astrophysics · Physics 2009-11-07 Daniela Carturan , Fabio Finelli

We extend the Chaplygin gas model for dark matter and dark energy unification by promoting the Chaplygin gas parameter A to the potential for an extra scalar with canonical kinetic energy. The hybrid model allows for accelerated Hubble…

Astrophysics · Physics 2009-11-10 Neven Bilic , Gary B. Tupper , Raoul D. Viollier

Although various cosmological observations congruously suggest that our universe is dominated by two dark components, the cold dark matter without pressure and the dark energy with negative pressure, the nature and origin of these…

Astrophysics · Physics 2009-11-10 Zong-Hong Zhu

We examine the properties of dark energy and dark matter through the study of the variation of the electromagnetic coupling. For concreteness, we consider the unification model of dark energy and dark matter, the generalized Chaplygin gas…

Astrophysics · Physics 2008-11-26 M. C. Bento , O. Bertolami , P. Torres

In this study, we investigate two dark energy models, MCJG and MCAG, in the context of $f(T)$ gravity within a non-flat FLRW Universe. Our analysis considers radiation, dark matter, and dark energy components. We compare the equation of…

General Relativity and Quantum Cosmology · Physics 2024-01-24 Himanshu Chaudhary , Ujjal Debnath , Tanusree Roy , Sayani Maity , G. Mustafa , Monika Arora