Qualitative evolution in f(R) cosmologies

TL;DR

This paper explores the qualitative behavior of higher-dimensional f(R) gravity cosmologies, analyzing various models and comparing Einstein and Jordan frames to understand their evolution and potential features.

Contribution

It provides a comprehensive analysis of the evolution of (D+1)-dimensional f(R) cosmologies, including specific models like Starobinsky and polynomial/exponential functions, in both Einstein and Jordan frames.

Findings

Different models exhibit distinct qualitative evolution patterns.

Negative regions in Einstein frame potentials influence cosmological dynamics.

Comparison between Einstein and Jordan frames reveals key differences in evolution.

Abstract

We investigate the qualitative evolution of (D+1)-dimensional cosmological models in f(R) gravity for the general case of the function f(R). The analysis is specified for various examples, including the (D+1)-dimensional generalization of the Starobinsky model, models with polynomial and exponential functions. The cosmological dynamics are compared in the Einstein and Jordan representations of the corresponding scalar-tensor theory. The features of the cosmological evolution are discussed for Einstein frame potentials taking negative values in certain regions of the field space.