Generalized second law of thermodynamics in f(R,T) theory of gravity

TL;DR

This paper investigates the validity of the generalized second law of thermodynamics within the f(R,T) gravity framework, analyzing how it depends on cosmological parameters and the specific form of f(T).

Contribution

It derives the geometric entropy form and establishes conditions for the second law's validity in f(R,T) gravity, extending thermodynamic analysis to modified gravity theories.

Findings

The geometric entropy form in f(R,T) gravity is derived.

Conditions for the generalized second law to hold are identified.

Relations depend on Hubble, deceleration parameters, and f(T) form.

Abstract

We present a study of the generalized second law of thermodynamics in the scope of the f(R,T) theory of gravity, with R and T representing the Ricci scalar and trace of the energy-momentum tensor, respectively. From the energy-momentum tensor equation for the f(R,T) = R + f(T) case, we calculate the form of the geometric entropy in such a theory. Then, the generalized second law of thermodynamics is quantified and some relations for its obedience in f(R,T) gravity are presented. Those relations depend on some cosmological quantities, as the Hubble and deceleration parameters, and on the form of f(T).