The definition of the Galileon gravity form is extended to the Brans-Dicke theory. Given, the framework of the Galileon theory, the generalized ghost dark energy model in an anisotropic universe is investigated. We st...The definition of the Galileon gravity form is extended to the Brans-Dicke theory. Given, the framework of the Galileon theory, the generalized ghost dark energy model in an anisotropic universe is investigated. We study the cosmological implications of this model. In particular, we obtain the equation of state and the deceleration parameters and a differential equation governing the evolution of this dark energy in Bianchi type I model. We also probe observational constraints by using the latest observational data on the generalized ghost dark energy models as the unification of dark matter and dark energy. In order to do so, we focus on observational determinations of the Hubble expansion rate(namely, the expansion history) H(z). As a result, we show the influence of the anisotropy(although low) on the evolution of the universe in the statefinder diagrams for Galileon gravity.展开更多
To scrutinize the nature of dark energy,many equations of state have been proposed.In this context,we examine the simplest parameterization of the equation of state parameter of dark energy in an anisotropic Bianchi t...To scrutinize the nature of dark energy,many equations of state have been proposed.In this context,we examine the simplest parameterization of the equation of state parameter of dark energy in an anisotropic Bianchi type I universe compared with theΛCDM model.Using different combinations of data samples,including Pantheon and Pantheon+H(z),alongside applying the minimization of theχ^(2)function of the distance modulus of data samples,we obtain the constrained values of cosmographic parameters in the parameterization of the dark energy scenario.One condition of the phantom barrier crossing is acquired.Several physical properties of the universe are discussed by considering the anisotropy effect and different observational data points.One should note that the deductions of the cosmological parameter verify recent observational data.展开更多
文摘The definition of the Galileon gravity form is extended to the Brans-Dicke theory. Given, the framework of the Galileon theory, the generalized ghost dark energy model in an anisotropic universe is investigated. We study the cosmological implications of this model. In particular, we obtain the equation of state and the deceleration parameters and a differential equation governing the evolution of this dark energy in Bianchi type I model. We also probe observational constraints by using the latest observational data on the generalized ghost dark energy models as the unification of dark matter and dark energy. In order to do so, we focus on observational determinations of the Hubble expansion rate(namely, the expansion history) H(z). As a result, we show the influence of the anisotropy(although low) on the evolution of the universe in the statefinder diagrams for Galileon gravity.
文摘To scrutinize the nature of dark energy,many equations of state have been proposed.In this context,we examine the simplest parameterization of the equation of state parameter of dark energy in an anisotropic Bianchi type I universe compared with theΛCDM model.Using different combinations of data samples,including Pantheon and Pantheon+H(z),alongside applying the minimization of theχ^(2)function of the distance modulus of data samples,we obtain the constrained values of cosmographic parameters in the parameterization of the dark energy scenario.One condition of the phantom barrier crossing is acquired.Several physical properties of the universe are discussed by considering the anisotropy effect and different observational data points.One should note that the deductions of the cosmological parameter verify recent observational data.
