Viscous dissipative Chaplygin gas dominated homogenous and isotropic cosmological models

Chaplygin gas dominated anisotropic brane world cosmological models

Viscous Generalized Chaplygin Gas

Viscous GCG(generalized Chaplygin gas) cosmology is discussed, assuming that there is bulk viscosity in the linear barotropic fluid and GCG. The dynamical analysis indicates that the phase wg = −1 + √ 3γκτg/(γ − √ 3κτγ) is a dynamical attractor and the equation of state of GCG approaches it from either wg > −1 or wg < −1 depending on the choice of its initial cosmic density parameter and the ra...

Anisotropic Cosmological Models with a Generalized Chaplygin Gas

Anisotropic cosmological models with a generalized Chaplygin gas in a Finsler space-time geometry are considered and a class of exact solutions as well as cosmological parameters behaviors are studied. Moreover, the viability and stability criteria for a general solution are also discussed.

Viscous dissipative effects in isotropic brane cosmology

We consider the dynamics of a viscous cosmological fluid in the generalized Randall-Sundrum model for an isotropic brane. To describe the dissipative effects we use the Israel-Hiscock-Stewart full causal thermodynamic theory. In the limiting case of a stiff cosmological fluid with pressure equal to the energy density, the general solution of the field equations can be obtained in an exact param...

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(...