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Related papers: Chaplygin gas halos

200 papers

We consider the scenario emerging from the dynamics of a generalized $d$-brane in a $(d+1, 1)$ spacetime. The equation of state describing this system is given in terms of the energy density, $\rho$, and pressure, $p$, by the relationship…

General Relativity and Quantum Cosmology · Physics 2009-11-07 M. C. Bento , O. Bertolami , A. A. Sen

The cosmological observations suggest that the presently accelerating universe should be filled by an exotic form of matter, violating the strong energy condition, of unknown nature and origin. We propose the viscous dark matter of a source…

General Relativity and Quantum Cosmology · Physics 2020-08-05 Marek Szydlowski , Adam Krawiec

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

Unified cosmological models have received a lot of attention in astrophysics community for explaining both the dark matter and dark energy evolution. The Chaplygin cosmologies, a well known name in this group have been investigated matched…

General Relativity and Quantum Cosmology · Physics 2019-10-09 Weiqiang Yang , Supriya Pan , Andronikos Paliathanasis , Subir Ghosh , Yabo Wu

The consequences of taking the generalized Chaplygin gas as the dark energy constituent of the Universe on the gravitational waves are studied and the spectrum obtained from this model, for the flat case, is analyzed. Besides its importance…

General Relativity and Quantum Cosmology · Physics 2009-11-10 J. C. Fabris , S. V. B. Goncalves , M. S. dos Santos

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

The nature of the dark components (dark matter and dark energy) that dominate the current cosmic evolution is a completely open question at present. In reality, we do not even know if they really constitute two separated substances. In this…

Astrophysics · Physics 2009-11-10 Abha Dev , Deepak Jain , J. S. Alcaniz

We employ the generalized Chaplygin gas of interacting dark energy to obtain the equation of state for the generalized Chaplygin gas energy density in non-flat universe. By choosing a negative value for $B$ we see that $w_{\rm…

General Relativity and Quantum Cosmology · Physics 2010-10-27 M R Setare

Unified dark matter cosmologies economically combine missing matter and energy in a single fluid. Of these models, the standard Chaplygin gas is theoretically motivated, but faces problems in explaining large scale structure if linear…

Cosmology and Nongalactic Astrophysics · Physics 2022-10-12 Abdelrahman Abdullah , Amr El-Zant , Ali Ellithi

In this paper, we consider three different models of dark energy in higher dimensional space-time and discuss about some cosmological parameters numerically. The first model is a single component universe including viscous varying modified…

General Relativity and Quantum Cosmology · Physics 2014-06-13 M. Khurshudyan , J. Sadeghi , M. Hakobyan , H. Farahani , R. Myrzakulov

Adaptive SPH and N-body simulations were carried out to study the effect of gasdynamics on the structure of dark matter halos that result from the gravitational instability and fragmentation of cosmological pancakes. Such halos resemble…

Astrophysics · Physics 2007-05-23 Marcelo Alvarez , Paul R. Shapiro , Hugo Martel

Hybrid Chaplygin gas model is put forward, in which the gases play the role of dark energy. For this model the coincidence problem is greatly alleviated. The effective equation of state of the dark energy may cross the phantom divide…

Astrophysics · Physics 2015-05-13 Hongsheng Zhang , Zong-Hong Zhu , Lihua Yang

We investigate cosmological scenarios of generalized Chaplygin gas in a universe governed by Horava-Lifshitz gravity. We consider both the detailed and non-detailed balance versions of the gravitational background, and we include the…

Cosmology and Nongalactic Astrophysics · Physics 2012-01-24 Amna Ali , Sourish Dutta , Emmanuel N. Saridakis , Anjan A. Sen

Recently developed Generalized Cosmic Chaplygin gas (GCCG) is studied as an unified model of dark matter and dark energy. To explain the recent accelerating phase, the Universe is assumed to have a mixture of radiation and GCCG. The mixture…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Writambhara Chakraborty , Ujjal Debnath , Subenoy Chakraborty

A modified Chaplygin gas model (MCG), $\rho_{MCG}/\rho_{MCG0}=[B_{s}+(1-B_{s})a^{-3(1+B)(1+\alpha)}]^{1/(1+\alpha)}$, as a unified dark matter model and dark energy model is constrained by using current available cosmic observational data…

Cosmology and Nongalactic Astrophysics · Physics 2012-04-26 Lixin Xu , Yuting Wang , Hyerim Noh

I present a model in which dark energy interacts with matter. The former is represented by a variable equation of state. It is shown that the phantom crossing takes place at zero redshift, moreover, stable scaling solution of the Friedmann…

High Energy Physics - Theory · Physics 2010-01-11 Mubasher Jamil

We consider an anisotropic brane-world model with Bianchi type I and V geometry, without mirror symmetry or any form of junction conditions. The generalized Chaplygin gas, which interpolates between a high density relativistic era and a…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Malihe Heydari-Fard , Hamid R. Sepangi

In this paper, viscous generalized Chaplygin gas as a model of dark energy considered. We assume non-constant bulk viscous coefficient and study dark energy density. We consider several cases of density-dependent viscosities. We find that,…

General Relativity and Quantum Cosmology · Physics 2014-03-10 H. Saadat , B. Pourhassan

In this paper we study a quintessence cosmological model in which the dark energy component is considered to be the Generalized Chaplygin Gas and the curvature of the three-geometry is taken into account. Two parameters characterize this…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Sergio del Campo , José Villanueva

The structure of dark matter halos as predicted from cosmological models is discussed and compared with observed rotation curves of dark matter-dominated dwarf galaxies. The theoretical models predict that dark matter halos represent a…

Astrophysics · Physics 2007-05-23 Andreas Burkert , Joseph Silk