Thermodynamics in new model of loop quantum cosmology

TL;DR

This paper extends the thermodynamic analysis of loop quantum cosmology to a new model including the Lorentz term, showing that effective density and pressure govern universe evolution and satisfy the first law of thermodynamics.

Contribution

It introduces a thermodynamic framework for the recent LQC model with the Lorentz term, linking effective quantities to thermodynamic laws.

Findings

Effective density and pressure determine universe dynamics.

The first law of thermodynamics holds with the Misner-Sharp energy.

Thermodynamic quantities have clear physical meaning in this model.

Abstract

The thermodynamic properties of loop quantum cosmology (LQC) without considering the Lorentz term were established in \cite{Zhu09}. In this paper, we extend this result to the recent proposed new model of LQC with the Lorentz term. We investigate the thermodynamics of LQC on the apparent horizon of the Friedmann-Lematre-Robertson-Walker universe. The result shows that the effective density and effective pressure in the modified Friedmann equation of LQC not only determines the evolution of the universe but can also serve as the thermodynamic quantities. Moreover, with the help of the Misner-Sharp energy, the first law of thermodynamics of the LQC is still valid as expected. This in turn endows precise physical meaning to the effective matter density $\rho_{eff}$ and the effective pressure $P_{eff}$.