发表机构
Universidad Veracruzana; Pontificia Universidad Católica de Valparaíso; National Observatory of Athens; Universidad Católica del Norte; University of Science and Technology of China（韦拉克鲁斯大学; 瓦尔帕莱索天主教 Pontificia 大学; 雅典国家天文台; 北天主教大学; 中国科学技术大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
研究以广义第二定律为热力学判据，推导动力学暗能量模型的视界熵渐近标度约束，验证其适用于多种宇宙学框架，可区分不同修改宇宙学模型。
AI 中文摘要
广义视界熵提案数量的日益增多催生了种类繁多的修改宇宙学模型，但目前尚无通用物理原理能够对这些模型进行区分。我们证明，热力学的广义第二定律（GSL）可作为此类判据。考虑由哈勃参数的任意函数 $f(H)$ 描述的一般修改弗里德曼框架，并允许表观视界与宇宙流体脱离热平衡演化，我们推导出视界熵渐近标度 $S_A \propto A^k$ 的模型无关约束条件。我们发现，幻影演化要求 $k\ge(3\omega-1)/(2\omega)$，其中 $\omega$ 为总流体物态方程参数；而 quintessence（精质）则施加互补的上界约束。此外，在精确热平衡极限下，动力学耦合严格要求 $k \le 2$，恢复了非平衡精质的约束。当接近幻影分界线时，这两个约束收敛于唯一值 $k=2$，表明幻影分界线的平滑跨越在热力学上与二次熵-面积标度相关，此时有效理论退化为对数引力框架。将该判据应用于代表性广义熵模型后发现，许多常用提案受到广义第二定律的约束，而多参数构造则自然符合所需的渐近行为。最后，我们证明相同的热力学选择原理可扩展至由 $f(H,\dot H)$ 描述的依赖导数的宇宙学，凸显其仅依赖视界面积的熵泛函之外的稳健性。
英文摘要
The growing number of generalized horizon entropy proposals has led to a wide variety of modified cosmological models, yet there is currently no general physical principle capable of discriminating among them. We show at the level of an homogeneous background that the generalized second law (GSL) of thermodynamics provides such a criterion. Considering a general modified Friedmann framework described by an arbitrary function $f(H)$ of the Hubble parameter, and allowing the apparent horizon and the cosmic fluid to evolve out of thermal equilibrium, we derive model-independent constraints on the asymptotic scaling of the horizon entropy, $S_A\propto A^k$. We find that phantom evolution requires $k\ge(3ω-1)/(2ω)$, with $ω$ the total fluid equation of state, whereas quintessence imposes the complementary upper bound. Additionally, in the exact thermal equilibrium limit, the dynamical coupling strictly enforces $k \le 2$, recovering the non-equilibrium quintessence bound. The two bounds converge to the unique value $k=2$ as the phantom divide is approached, indicating that a smooth crossing of the phantom divide is thermodynamically associated with a quadratic entropy-area scaling, where the effective theory degenerates into a logarithmic gravity framework. Applying this criterion to representative generalized entropy models shows that many commonly used proposals are constrained by the generalized second law, whereas multiparameter constructions are naturally compatible with the required asymptotic behavior. Finally, we demonstrate that the same thermodynamic selection principle extends to derivative-dependent cosmologies described by $f(H,\dot H)$, highlighting its robustness beyond entropy functionals that depend only on the horizon area.
Comments15 pages, 1 figure. Published version in PDU
Journal refPhys. Dark Univ. 54, 102475 (2026)
DOI：10.1016/j.dark.2026.102475
