Observational Constraints on Variable Chaplygin Gas
نویسندگان
چکیده
We investigate observational constraints on the variable Chaplygin gas model from the gold sample of type Ia supernova data and the recent measurements of the X-ray gas mass fractions in galaxy clusters. Combining these databases, we obtain a tight constraint on the two model parameters. Our results indicate that the original Chaplygin gas model is ruled out by the data at 99.7% confidence level. ∗e-mail address: [email protected]
منابع مشابه
Generalized Chaplygin gas as a unified scenario of dark matter/energy: observational constraints
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 components is yet unknow. The generalized Chaplygin gas (gCg), parametrized by an equation of state, p = −A/ραgCg, was recently proposed to be a candidate of the unif...
متن کاملObservational Constraints on the Generalized Chaplygin Gas
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 sort of fluid, the ν and the α parameters. We use different astronomical data for restricting these parameters. It is shown that the constraint ν . α agrees en...
متن کاملInteracting Modified Variable Chaplygin Gas in a Non-flat Universe
We have presented a more generalized model of interacting Chaplygin gas. The effective equation of states corresponding to matter and dark energy have been derived in this generalized model. Moreover, the case of phantom energy arises by putting some constraints on the parameters involved.
متن کاملHolographic Dark Energy Scenario and Variable Modified Chaplygin Gas
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...
متن کاملVariable Chaplygin Gas
We consider a variable Chaplygin gas model, which is characterized by an exotic equation of state, P = −A(a)/ρ, where A(a) is a positive function of the scale factor. By assuming a power-law function A(a) we find that the variable Chaplygin gas evolves as from dust to quiessence. We show that the model is consistent with current type Ia supernova data for a broad range of parameters. ∗e-mail ad...
متن کامل