Interacting dark fluid in the universe bounded by event horizon : A non-equilibrium prescription

TL;DR

This paper investigates the non-equilibrium thermodynamics of interacting dark matter and dark energy within the universe bounded by the event horizon, analyzing heat flow and the validity of the generalized second law of thermodynamics.

Contribution

It introduces a non-equilibrium thermodynamic framework for interacting dark sectors with different dark energy models and tests the generalized second law in this context.

Findings

Heat flow indicates deviation from thermal equilibrium.

Generalized second law holds under certain conditions.

Different dark energy models affect thermodynamic behavior.

Abstract

A non-equilibrium thermodynamic analysis has been done for the interacting dark fluid in the universe bounded by the event horizon.From observational evidences it is assumed that at present the matter in the universe is dominated by two dark sectors-dark matter and dark energy. The mutual interaction among them results in spontaneous heat flow between the horizon and the fluid system and the thermal equilibrium will no longer hold.In the present work,the dark matter is chosen in the form of dust while the dark energy is chosen as a perfect fluid with constant equation in one case and holographic dark energy model is chosen in the other.Finally,validity of the generalized second law of thermodynamics has been examined in both cases.