LRS Bianchi type-V universe with variable modified Chaplygin gas in a scalar–tensor theory of gravitation

The spatially homogeneous and anisotropic LRS Bianchi type-V Universe filled with variable modified Chaplygin gas in the framework of the Brans–Dicke (Brans and Dicke. Phys. Rev. 124, 925 (1961). doi:10.1103/PhysRev.124.925) scalar–tensor theory of gravitation has been studied. To obtain a determinate solution of the field equations we have used the condition that scalar field ([Formula: see text]) is a function of average scale factor. Some physical and kinematical properties of the model are discussed. We have also analyzed the stability of the solution.

Cosmological constraints on the variable modified Chaplygin gas model by using MCMC approach

We investigate the cosmological constraints on the variable modified Chaplygin gas (VMCG) model from the latest observational data: Union2 dataset of Type Ia supernovae (SNIa), the observational Hubble data (OHD), the baryon acoustic oscillations (BAO) and the cosmic microwave background (CMB) data. By using the Markov chain Monte Carlo (MCMC) method, we obtain the mean values of parameters in the flat model: [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text] and [Formula: see text]. Furthermore, we investigate the thermodynamical properties of VMCG model at apparent horizon, event horizon and particle horizon respectively.