Accelerating universe with variable EoS parameter of dark energy in Bransa??Dicke theory of gravitation

摘要

We have investigated the spatially homogeneous and isotropic Friedmanna??Robertsona??Walker (FRW) universe filled with barotropic fluid and dark energy in the framework of the Bransa??Dicke theory of gravitation. Here we have discussed three models: (i) law of variation for Hubblea??s parameter, which leads to a constant value of deceleration parameter, (ii) hybrid expansion law model, and (iii) special form of deceleration parameter model. We have found that among all these derived models, the most suitable standard cosmological model according to the recent cosmological observations is the model with special form of deceleration parameter.