Thermodynamic descriptions of Polytropic gas and its viscous type as the dark energy candidates

TL;DR

This paper explores the thermodynamics of polytropic and viscous polytropic dark energy models in a FRW universe, examining their interactions, entropy corrections, and implications for cosmic evolution.

Contribution

It introduces a thermodynamic framework for viscous polytropic dark energy, linking thermal fluctuations to dark sector interactions and entropy corrections.

Findings

Thermal fluctuations relate to dark energy-dark matter interactions.

Viscous effects modify horizon entropy and second law considerations.

Conditions for dark energy decay into dark matter are identified.

Abstract

In this paper, at first, we focus on a FRW universe in which the dark energy candidate satisfies the Polytropic equation of state and study thermodynamics of dark energy. Bearing the thermal fluctuation theorem in mind, we establish a relation between the thermal fluctuation of system and mutual interaction between the dark energy and dark matter. Generalization to a viscous Polytropic gas is also investigated. We point to a condition for decaying dark energy candidate into the dark matter needed for alleviating coincidence problem. The effects of dark energy candidates and their interactions with other parts of cosmos on the horizon entropy as well as the second law of thermodynamics are also addressed. Our study signals us to a correction term besides the Bekenstein entropy which carries the information of the dark energy candidate, its interaction with other parts of cosmos and its viscosity.