# Qualitative behavior of cosmological models combining various matter fields

## TL;DR

This paper analyzes the qualitative behavior of cosmological models with a mixture of matter, dark matter, and scalar fields, using dynamical systems to understand the universe's accelerated expansion and evolution.

## Contribution

It introduces a dynamical system framework for multi-fluid cosmological models, highlighting the role of effective equation of state in understanding cosmic acceleration.

## Key findings

- Stability analysis identifies dominant fluids during different cosmic epochs.
- The model explains transition phases between matter, dark matter, and dark energy dominance.
- The approach links fluid domination to universe acceleration phases.

## Abstract

The late time accelerated expansion of the universe can be realized using scalar fields with given self-interacting potentials. Here we consider a straightforward approach where a three cosmic fluid mixture is assumed. The fluids are standard matter perfect fluid, dark matter, and a scalar field with the role of dark energy. A dynamical system analysis is developed in this context. A central role is played by the equation of state $\omega_{eff}$ which determines the acceleration phase of the models. Determining the domination of a particular fluid at certain stages of the universe history by stability analysis allows, in principle, to establish the succession of the various cosmological eras.