论文标题
主动物质中的不可逆性：主动Ornstein-Uhlenbeck颗粒的一般框架
Irreversibility in active matter: General framework for active Ornstein-Uhlenbeck particles
论文作者
论文摘要
主动物质系统通过将能量转换为各个成分水平的定向运动而从平衡中驱动。本着最少的描述的精神，活动物质通常由所谓的活跃的Ornstein-uhlenbeck颗粒（AOUPS）建模，这是被动性布朗运动的扩展，其中活性由其他具有简单统计特性的非平衡“力”来表示。尽管在被动的布朗运动中，沿轨迹的熵产生众所周知，众所周知，与观察到时间倒转的双胞胎轨迹相比，概率的对数记录相比，概率的对数比率是不可逆的，因此，这些概念之间的连接对于活动物质而言较不明显。因此，仅基于可测量量（例如粒子位置），为活动粒子轨迹的不可逆性提供明确的表达至关重要。在此技术说明中，我们从路径概率比（向后路径与向后路径）方面得出了AOUP的不可逆性的一般表达，从而扩大了[PRX 9，021009（2019）]的最新结果，通过允许任意的初始粒子分布和活性驱动的状态。
Active matter systems are driven out of equilibrium by conversion of energy into directed motion locally on the level of the individual constituents. In the spirit of a minimal description, active matter is often modeled by so-called active Ornstein-Uhlenbeck particles (AOUPs), an extension of passive Brownian motion where activity is represented by an additional fluctuating non-equilibrium "force" with simple statistical properties (Ornstein-Uhlenbeck process). While in passive Brownian motion, entropy production along trajectories is well-known to relate to irreversibility in terms of the log-ratio of probabilities to observe a certain particle trajectory forward in time in comparison to observing its time-reversed twin trajectory, the connection between these concepts for active matter is less clear. It is therefore of central importance to provide explicit expressions for the irreversibility of active particle trajectories based on measurable quantities alone, such as the particle positions. In this technical note, we derive a general expression for the irreversibility of AOUPs in terms of path probability ratios (forward versus backward path), extending recent results from [PRX 9, 021009 (2019)] by allowing for arbitrary initial particle distributions and states of the active driving.
