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arXiv · 1804.00772

Apparent horizon and gravitational thermodynamics of Universe in the Eddington-Born-Infeld theory

Jia-Cheng Ding·Qi-Qi Fan·Cong Li·Ping Li·Jian-Bo Deng
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Abstract

The thermodynamics of Universe in the Eddington-Born-Infeld (EBI) theory was restudied by utilizing the holographic-style gravitational equations that dominate the dynamics of the cosmical apparent horizon $Υ_{A}$ and the evolution of Universe. We started in rewriting the EBI action of the Palatini approach into the Bigravity-type action with an extra metric $q_{μν}$. With the help of the holographic-style dynamical equations, we discussed the property of the cosmical apparent horizon $Υ_{A}$ including timelike, spacelike and null characters, which depends on the value of the parameter of state $w_{m}$ in EBI Universe. The unified first law for the gravitational thermodynamics and the total energy differential for the open system enveloped by $Υ_{A}$ in EBI Universe were obtained. Finally, applying the positive-heat-out sign convention, we derived the generalized second law of gravitational thermodynamics in EBI universe.

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Jia-Cheng Ding, Qi-Qi Fan, Cong Li, Ping Li, Jian-Bo Deng. 2019-01-01. Apparent horizon and gravitational thermodynamics of Universe in the Eddington-Born-Infeld theory. https://doi.org/10.1155/2018%2F7801854

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