Pole-skipping and many-body quantum chaos

Recent developments have indicated that in addition to out-of-time ordered correlation functions (OTOCs), quantum chaos also has a sharp manifestation in the thermal energy density two-point functions, at least for maximally chaotic systems. The manifestation, referred to as pole-skipping, concerns the analytic behaviour of energy density two-point functions around a special point in the complex frequency and momentum plane. I will first describe the mathematical description of pole-skipping in holographic theories and then explain how this phenomenon provides a novel connection between hydrodynamics and chaos.