Nonequilibrium Apparent-Horizon Thermodynamics in Effective Loop Quantum Cosmology

Xiao Liu

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arXiv · 2609.13720

Nonequilibrium Apparent-Horizon Thermodynamics in Effective Loop Quantum Cosmology

Xiao Liu

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Abstract

In this work, we investigate the thermodynamic consistency of the apparent horizon in effective loop quantum cosmology (LQC). By retaining the standard definitions of horizon thermodynamic quantities, we find that the modified LQC dynamics leads to a departure from the classical equilibrium thermodynamic description. This deviation can be naturally described by a nonequilibrium formulation characterized by an internal entropy production term. The resulting entropy production consistently recovers the classical and de Sitter limits. These results suggest that the apparent horizon in effective LQC admits a coherent nonequilibrium thermodynamic interpretation.

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Xiao Liu. 2026-09-12. Nonequilibrium Apparent-Horizon Thermodynamics in Effective Loop Quantum Cosmology. https://arxiv.org/abs/2609.13720

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