IPB Colloquium by Koenraad Schalm

The IPB colloquium will be held on Tuesday, 20 March 2018 at 11:00 in the “Zvonko Marić” lecture hall of the Institute of Physics Belgrade. The talk entitled

"(Quantum) Chaos, hydrodynamics, and black hole scrambling"

will be given by Prof. Koenraad Schalm (Lorentz Institute for Theoretical Physics, Leiden University, The Netherlands).

Abstract of the talk:

A concrete definition of chaos in quantum systems is a regime of exponential growth in a specific out-of-time-ordered correlator (OTOC). We will discuss this both in weakly coupled and in strongly coupled theories. In strongly coupled quantum theories with a holographic dual, the OTOC is directly related to probing the system's hydrodynamic sound modes. The information contained in the OTOC is dual to a gravitational shock wave and this can be reconstructed in terms of purely diffusion-like gravitational waves at the horizon of a single-sided black hole with specific regularity-enforced imaginary values of frequency and momentum. The fact that late-time equilibration and early-time chaos are controlled by the same dynamics is also a property of classical dilute gases. For weakly coupled systems, we show that the information contained in the OTOC follows from a Boltzmann kinetic equation for total energy exchange.