Speaker
Description
I will describe dynamical phase transitions as transitions occurring within the temporal fluctuations of time-additive observables in stochastic systems. These transitions manifest when a critical time scale within the system diverges, resulting in non-analytical behaviour in the large deviation function, akin to the role of free energy, of the specific observable studied. This critical time scale is pivotal in observing the system's relaxation towards stationarity and showcases the ergodicity of the system at criticality. Additionally, in cases where the dynamical phase transition is of the first order, I will show, particularly with random walks on graphs, that the critical behaviour of the system oscillates intermittently between phases, with the waiting time to transition from one phase to another serving as the key diverging time scale.
