The Perturbation of Material Density in F(R) Modified Gravity of Polynomial Exponential Form

This paper investigates the linear perturbation of material density of universe in f(R) modified gravity of polynomial exponential form on the scale of distance below the cosmic horizon (sub-horizon). The results show that the model for the evolution of universe is slightly different from that in the ΛCDM standard cosmological model. These can be used to show the difference of this modified gravitational model with the ΛCMD standard cosmological model and other cosmological models. We also investigate the ration of Ψ/ Φ and G eff / G N in the model and show that they are within allowable limits of experiments. Keywords: Linear perturbation; modified gravity; polynomial exponential form; material density of universe. DOI : 10.7176/APTA/78-05 Publication date :June 30 th 2019