# Spatially-Flat Robertson-Walker models with combined CDM and stiff matter sources and the corresponding thermodynamics

## TL;DR

This paper analyzes a flat cosmological model with stiff matter and dust, deriving the scale factor and thermodynamic relations, including the equation of state, energy density, and pressure dependence on temperature.

## Contribution

It introduces a combined stiff matter and dust model with thermodynamic analysis, deriving explicit relations for energy density and pressure as functions of temperature.

## Key findings

- Derived the scale function and cosmological parameters.
- Obtained the general form of the equation of state.
- Established explicit temperature dependence of energy density and pressure.

## Abstract

In the present paper, we are considering a spatially-flat Friedmann-Robertson-Walker cosmological model, fueled with stiff matter and dust, treated as non-interacting ideal fluid sources. By solving the corresponding Friedmann equation with a non-zero cosmological constant, we are deriving the scale function and the fundamental cosmological parameters. Within a thermodynamic approach, the general form of the Equation of State is obtained, together with the explicit dependence of the energy density and pressure on temperature.

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Source: https://tomesphere.com/paper/1704.08036