The universe dominated by the extended Chaplygin gas

Density Perturbations in an Universe Dominated by the Chaplygin Gas

We study the fate of density perturbations in an Universe dominate by the Chaplygin gas, which exhibit negative pressure. We show that it is possible to obtain the value for the density contrast observed in large scale structure of the Universe by fixing a free parameter in the equation of state of this gas. The negative character of pressure must be significant only very recently. PACS number(...

Mass Power Spectrum in a Universe Dominated by the Chaplygin Gas

The mass power spectrum for a Universe dominated by the Chaplygin gas is evaluated numerically from scales of the order of the Hubble horizon to 100 Mpc. The results are compared with a pure baryonic Universe and a cosmological constant model. In all three cases, the spectrum increases with k, the wavenumber of the perturbations. The slope of the spectrum is higher for the baryonic model and sm...

Variable Modified Chaplygin Gas and Accelerating Universe

In this letter, I have proposed a model of variable modified Chaplygin gas and shown its role in accelerating phase of the universe. I have shown that the equation of state of this model is valid from the radiation era to quiessence model. The graphical representations of statefinder parameters characterize different phase of evolution of the universe. All results presented in the letter concer...

Chaplygin Gas Cosmology Predicts Only 'dusty' Universe

We consider a new approach for Chaplygin gas cosmology, in which the relativistic formulation of Chaplygin matter is of crucial importance. Specifically, the dynamical content of this matter induces a generalizd energy conservation principle. Our results show that (for all times) the universe consists of a novel form of matter with dust like density (∼ (volume) −1) and negative pressure, that i...

Chaplygin gas dominated anisotropic brane world cosmological models