# Bifurcations in Ratra-Peebles quintessence models and their extensions

## TL;DR

This paper uses bifurcation theory to analyze cosmological models with scalar fields, revealing generic evolution paths that explain both early inflation and late-time acceleration without initial singularities.

## Contribution

It applies bifurcation theory to scalar field cosmology, identifying generic evolution scenarios that unify inflation and late acceleration.

## Key findings

- Universe evolves from static or deSitter states to deSitter without singularities
- Inflation emerges endogenously from the model's dynamics
- Models unify early and late-time cosmic acceleration

## Abstract

We have used the dynamical system approach in order to investigate the dynamics of cosmological models of the flat Universe with a non-minimally coupled canonical and phantom scalar field and the Ratra-Peebles potential. Applying methods of the bifurcation theory we have found three cases for which the Universe undergoes a generic evolution emerging from either the deSitter or the static Universe state and finishing at the deSitter state, without the presence of the initial singularity. This generic class of solutions explains both the inflation and the late-time acceleration of the Universe. In this class inflation is an endogenous effect of dynamics itself.