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arXiv · 2406.09036

Thermodynamic of the $f(Q)$ universe

Haomin Rao·Chunhui Liu·Chao-Qiang Geng
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Abstract

We investigate thermodynamics of apparent horizon in the $f(Q)$ universe with trivial and nontrivial connections. We first explore the perspectives of the first law, generalized second law and $P-V$ phase transition with trivial connection. We show that the lowest-order correction of entropy has the same form as that in loop quantum gravity, and the critical exponents of the phase transition caused by the lowest-order correction are consistent with those in mean field theory. We then examine the thermodynamic implication of nontrivial connections. We find that nontrivial connections in the $f(Q)$ universe imply non-equilibrium states from the perspective of thermodynamics.

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Haomin Rao, Chunhui Liu, Chao-Qiang Geng. 2024-06-13. Thermodynamic of the $f(Q)$ universe. https://arxiv.org/abs/2406.09036

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