In this paper, the model of the holographic Chaplygin gas has been extended to two general cases: first the case of a modified variable Chaplygin gas and second the case of the viscous generalized Chaplygin gas. The dynamics of the model is expressed by the use of scalar fields and scalar potentials.

In this letter, we have considered that the universe is filled with normal matter and variable modified Chaplygin gas. Also we have considered the interaction between normal matter and variable modified Chaplygin gas in FRW universe. Then we have considered a correspondence between the holographic dark energy density and interacting variable modified Chaplygin gas energy density. Then we have r...

We review the essential features of the Chaplygin gas cosmological models and provide some examples of appearance of the Chaplygin gas equation of state in modern physics. A possible theoretical basis for the Chaplygin gas in cosmology is discussed. The relation with scalar field and tachyon cosmological models is also considered.

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 for the study of the primordial Universe, the gravitational waves represent an additional perspective (besides the CMB temperature and polarization anisotro...

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, pX = −A/ρ α X (a polytropic gas with negative constant and exponent). Our main result is that, restricting to a flat universe and to adiabatic pressure perturbations for the generalized Chaplygin ga...

We consider a new generalized Chaplygin gas model that includes the original Chaplygin gas model as a special case. In this model the generalized Chaplygin gas evolves as from dust to quiessence or phantom. We show that the model is consistent with current type Ia supernova data for a broad range of parameters. PACS number(s): 98.80.Es, 98.80.Cq ∗e-mail address: [email protected]

Perturbations in a Chaplygin gas, characterized by an equation of state p = −A/ρ, may acquire non-adiabatic contributions if spatial variations of the parameter A are admitted. This feature is shown to be related to a specific internal structure of the Chaplygin gas. We investigate how perturbations of this type modify the adiabatic sound speed and influence the time dependence of the gravitati...

We investigate the possibility of constraining Chaplygin dark energy models with current Integrated Sachs Wolfe effect data. In the case of a flat universe we found that generalized Chaplygin gas models must have an energy density such that Ωc > 0.55 and an equation of state w < −0.6 at 95% c.l.. We also investigate the recently proposed Silent Chaplygin models, constraining Ωc > 0.55 and w < −...

We provide a rigorous derivation of the evolution equation in the context of Chaplygin gas cosmology, in which the relativistic formulation of Chaplygin matter is a crucial ingredient. This is in contrast to the existing literature where the non-relativistic form of the Chaplygin equation of state is naively used in the covariant Einsstein equation. Our results show that the Chaplygin model des...

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...