Thermodynamics and dark energy

TL;DR

This paper explores the thermodynamic properties of dark energy, assuming it consists of massless quanta with a variable equation-of-state, and derives constraints on its parameters using observational and thermodynamic data.

Contribution

It introduces a thermodynamic analysis of dark energy with a general time-dependent equation-of-state, providing new bounds on its parameters based on combined data.

Findings

Stringent bounds on $w_0$ - $w_a$ parameter space

Thermodynamic constraints complement observational data

Dark energy properties can be constrained by thermodynamics

Abstract

A significant observational effort has been directed to unveil the nature of the so-called dark energy. However, given the large number of theoretical possibilities, it is possible that such a task cannot be performed on the basis only of the observational data. In this article we discuss some thermodynamic properties of this energy component by assuming that its constituents are massless quanta with a general time-dependent equation-of-state parameter $\omega(z)=\omega_0 + \omega_a f(z)$, where $\omega_0$ and $\omega_a$ are constants and $f(z)$ may assume different forms. We show that very restrictive bounds can be placed on the $w_0$ - $w_a$ space when current observational data are combined with the thermodynamic constraints derived.