Dynamical large deviations and phase separation in systems of interacting particles

我们将大偏差理论应用于相互作用粒子系统中的动力学涨落。大偏差理论描述了罕见事件的概率：这里我们关注的是系统在很长一段时间内没有遍历行为的事件。最近的工作已经证实，这样的事件可以伴随着宏观粒子团的形成：即相分离。这种相共存的理论地位仍然是个谜：它似乎违反了两相之间的压力(和化学势)相等等平衡定律。我们试图了解压力和化学势在这种状态下的作用。活性物质中也有可能与运动诱导的相分离有关，我们将对此进行研究。

We apply large deviation theory to dynamical fluctuations in interacting particle systems. Large deviation theory describes the probabilities of rare events: we focus here on events in which a system does not behave ergodically, over a long time period. Recent work has established that such events can be accompanied by the formation of a macroscopic cluster of particles: that is, phase separation. The theoretical status of this phase coexistence remains mysterious: it seems to violate equilibrium laws such as equality of pressure (and chemical potential) between the two phases. We seek to understand the role of pressure and chemical potential in this state. There are also possible connections with motility-induced phase separation in active matter, which we will investigate.