标题： 远离平衡态：理解宇宙学向低熵状态的演化 显示英文标题

标题： Out of equilibrium: understanding cosmological evolution to lower-entropy states

摘要： 尽管热力学第二定律十分重要，但它并非绝对成立。统计力学表明，在足够长的时间内，接近平衡态的系统会自发地波动到低熵状态，从而在局部逆转热力学的时间箭头。我们研究了这类波动的时间演化，特别是与宇宙学相关的大幅波动。在相当普遍的假设下，一个非平衡态波动最可能的历史轨迹仅仅是系统回到平衡态时最可能方式的CPT共轭。我们利用这一思想来阐明稳定和亚稳态de Sitter空间以及热反de Sitter空间中各种波动的时空结构。 显示英文摘要

摘要： Despite the importance of the Second Law of Thermodynamics, it is not absolute. Statistical mechanics implies that, given sufficient time, systems near equilibrium will spontaneously fluctuate into lower-entropy states, locally reversing the thermodynamic arrow of time. We study the time development of such fluctuations, especially the very large fluctuations relevant to cosmology. Under fairly general assumptions, the most likely history of a fluctuation out of equilibrium is simply the CPT conjugate of the most likely way a system relaxes back to equilibrium. We use this idea to elucidate the spacetime structure of various fluctuations in (stable and metastable) de Sitter space and thermal anti-de Sitter space.