Institute of Theoretical Physics, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland.
Phys Rev Lett. 2011 May 27;106(21):210601. doi: 10.1103/PhysRevLett.106.210601. Epub 2011 May 23.
The fluctuation theorem is a pivotal result of statistical physics. It quantifies the probability of observing fluctuations which are in violation of the second law of thermodynamics. More specifically, it quantifies the ratio of the probabilities of observing entropy-producing and entropy-consuming fluctuations measured over a finite volume and time span in terms of the rate of entropy production in the system, the measurement volume, and time. We study the fluctuation theorem in computer simulations of planar shear flow. The simulations are performed by employing the method of multiparticle collision dynamics, which captures both thermal fluctuations and hydrodynamic interactions. The main outcome of our analysis is that the fluctuation theorem is verified at any averaging time provided that the measurement volume exhibits a specific dependence on a hydrodynamic time scale.
涨落定理是统计物理学的一个关键结果。它定量地描述了观察违反热力学第二定律的涨落的概率。更具体地说，它定量地描述了在有限的体积和时间跨度内观察到的熵产生和熵消耗涨落的概率比，这是根据系统的熵产生率、测量体积和时间来衡量的。我们在平面剪切流的计算机模拟中研究了涨落定理。模拟采用多粒子碰撞动力学方法进行，该方法同时捕捉了热涨落和流体动力学相互作用。我们分析的主要结果是，只要测量体积表现出与流体力学时间尺度的特定依赖性，那么在任何平均时间内都可以验证涨落定理。
