Mike Blake

Hydrodynamics and Chaos in Quantum Matter

In this talk I will discuss how studies of holographic theories have led to the discovery of new connections between hydrodynamics and chaos in quantum many-body systems. In the first half of this talk I will describe evidence for a surprising relationship between the energy diffusion constant of strongly interacting theories and the butterfly velocity, which describes the speed at which many-body chaos propagates. In the second half of the talk I will discuss more recent developments that have led to a more precise relation between the energy density Green’s function of maximally chaotic systems and out-of-time ordered correlation functions. This new relation, known as `pole-skipping’, implies that chaos provides non-perturbative constraints on the dispersion relations of hydrodynamic collective modes in such systems.