论文标题
主动物质：量化均衡的出发
Active matter: quantifying the departure from equilibrium
论文作者
论文摘要
主动物质系统在单个成分水平的水平上被驱逐出来。一个被广泛研究的类是Athermal颗粒的系统，这些系统在粒子间相互作用和自我prop的综合影响下移动，而后者根据Ornstein-Uhlenbeck随机过程而演变。从直觉上讲，这些所谓的活跃的Ornstein-Uhlenbeck颗粒（AOUPS）系统与较长的自我强化持久性时间相距更远。定量地，这是通过增加的相等速度相关性（在平衡方面微不足道的）以及对自我扩散和迁移系数之间的爱因斯坦关系的增加来证实这一点。相反，根据位置空间轨迹的概率及其时间倒流的概率比率计算得出的熵生产速率，其对持久时间的非单调依赖性。因此，它无法正确量化AOUPS系统从平衡中的偏离。
Active matter systems are driven out of equilibrium at the level of individual constituents. One widely studied class are systems of athermal particles that move under the combined influence of interparticle interactions and self-propulsions, with the latter evolving according to the Ornstein-Uhlenbeck stochastic process. Intuitively, these so-called active Ornstein-Uhlenbeck particles (AOUPs) systems are farther from equilibrium for longer self-propulsion persistence times. Quantitatively, this is confirmed by the increasing equal-time velocity correlations (which are trivial in equilibrium) and by the increasing violation of the Einstein relation between the self-diffusion and mobility coefficients. In contrast, the entropy production rate, calculated from the ratio of the probabilities of the position space trajectory and its time-reversed counterpart, has a non-monotonic dependence on the persistence time. Thus, it does not properly quantify the departure of AOUPs systems from equilibrium.
