Homogeneous cosmologies in generalized modified gravity

TL;DR

This paper uses dynamical systems to analyze the stability of flat homogeneous cosmologies in a broad class of generalized modified gravity models, extending previous $F(R)$ studies to include arbitrary geometric invariants.

Contribution

It generalizes stability analysis methods from $F(R)$ gravity to models with arbitrary geometric invariants, providing comprehensive critical point equations.

Findings

Derived general equations for critical points in these models

Extended stability analysis beyond $F(R)$ gravity

Applicable to models with various geometric invariants

Abstract

Dynamical system methods are used in the study of the stability of spatially flat homogeneous cosmologies within a large class of generalized modified gravity models in the presence of a relativistic matter-radiation fluid. The present approach can be considered as the generalization of previous works in which only $F(R)$ cases were considered. Models described by an arbitrary function of all possible geometric invariants are investigated and general equations giving all critical points are derived.