Modified cosmology from the thermodynamics of apparent horizon
Abstract
In the realm of the Bekenstein-Hawking entropy, the thermodynamics of apparent horizon bridges with the usual FLRW (Friedmann-Lema\^{i}tre-Robertson-Walker) equation only for a special case where the matter field is given by a perfect fluid having equation of state (EoS) parameter , i.e with and represent the energy density and the pressure of the fluid, respectively. To include the case , we consider the modification of the Bekenstein-Hawking entropy in the present work. In particular, we develop an entropy function that leads to the usual FLRW equations, for a EoS of the matter fluid given by , directly from the thermodynamics of the apparent horizon. The newly developed entropy acquires a correction over the Bekenstein-Hawking entropy and differs from the known entropies like the Tsallis, R\'{e}nyi, Barrow, Sharma-Mittal, Kaniadakis, and Loop Quantum Gravity entropies proposed so far. Based on this finding, we examine how the Friedmann equations of the apparent horizon cosmology are accordingly modified if one starts with a general entropy depending on the Bekenstein-Hawking entropy. This results in some interesting cosmological consequences during the early and late stages of the universe.
Keywords
Cite
@article{arxiv.2211.02822,
title = {Modified cosmology from the thermodynamics of apparent horizon},
author = {Shin'ichi Nojiri and Sergei D. Odintsov and Tanmoy Paul},
journal= {arXiv preprint arXiv:2211.02822},
year = {2022}
}
Comments
Physics Letters B (PLB) accepted