Inflation and dark energy in f (R, X, phi) gravity

Abstract

In this study, we show the early inflation and the late-time acceleration of the universe in the model R + alpha R-n - beta R2-n + f(X, phi), which shows a minimum connection between geometry and scalar field. Both a quintessential inflation and the super inflation mechanism are discussed in the model, and for both the cases the some conditions for n are obtained under the constraint of the observational data. However, the oscillations of the scalar field are analyzed in view of observational constraints. By means of the oscillations of the scalar field, besides the inflation of the universe a condition of n for the late-time quintessence type of dark energy is obtained.