Quantum order at infinite temperature, time crystals, and dissipation
Abstract: Discrete time crystals is the name given to many-body systems displaying long-time dynamics that is sub-harmonic with respect to a driving frequency. While these were first discussed in closed quantum systems a few years ago, recent work (partly motivated by experiments) has focussed on including non-unitary effects such as due to an external environment ("dissipation"). In this talk I will describe one of the unitary models, then possibly discuss a general framework for subharmonic oscillations stabilised by dissipative dynamics. The unitary and non-unitary phenomena are conceptually distinct.