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arXiv · 2111.00726

Emergence of space from non-equilibrium thermodynamics in f(R) gravity

Hassan Basari V. T.·P. B. Krishna·Titus K. Mathew
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Abstract

It has shown that the accelerated expansion of the FRW Universe can be explained as the quest towards the holographic equipartition ($N_{sur} = N_{bulk}$), satisfies the expansion law $\frac{dV}{dt} = l_{P}^{2} \left( N_{sur} - \epsilon N_{bulk} \right)$, from which one can derive the Friedmann equation of the FRW Universe in Einstein gravity \cite{paddy2012jun}. We introduce a generic derivation of the expansion law from the generalized first law of thermodynamics $-dE=TdS$ and $dE=TdS + WdV$. The generic derivation provides an expression for $N_{sur}$ in terms of entropy $S$ and the expansion law consistent with gravity theories having different entropy $S$, like Gauss-Bonnet and more general Lovelock gravity. We extended the same idea to the non-equilibrium situation and obtained the expansion law in f(R) gravity as a specific case. For this, we used the first law of thermodynamics in non-equilibrium description having the extra entropy production term $Td_{i}S.$

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Hassan Basari V. T., P. B. Krishna, Titus K. Mathew. 2021-11-01. Emergence of space from non-equilibrium thermodynamics in f(R) gravity. https://arxiv.org/abs/2111.00726

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