The generalized second law in chameleon cosmology

TL;DR

This paper examines the validity of the generalized second law of thermodynamics within flat FRW chameleon cosmology, focusing on entropy behavior during universe contraction and the influence of cosmological parameters.

Contribution

It provides an analysis of the GSL in chameleon cosmology, especially during bouncing scenarios with phantom crossing, highlighting entropy dynamics in different cosmic epochs.

Findings

Total entropy decreases during the contracting epoch.

Entropy behavior depends on the equation of state and Hubble parameters.

The validity of GSL varies with cosmic phase and model parameters.

Abstract

In this paper, we investigate the validity of the generalized second law (GSL) of thermodynamics in flat FRW chameleon cosmology where the boundary of the universe is assumed to be enclosed by the dynamical apparent horizon. It has been shown that, in a bouncing scenario for the universe with phantom crossing, the total entropy decreases with time in the contracting epoch, whereas, the dynamics of the internal and horizon entropies depends on the behavior of both equation of state and hubble parameters.