Explore the hydrodynamic scale for integrable classical many-body systems in this 30-minute conference talk by Herbert Spohn, recorded as part of the 2021 Non-Equilibrium Universality in Many-Body Physics KITP Conference. Delve into topics such as generalized free energy, CMV matrices, operator image, and legs filter. Gain insights into the intersection of statistical physics, AMO, condensed matter, and high-energy physics as Spohn discusses novel phases of matter far from equilibrium and their associated universality classes. Examine the dialogue between diverse scientific communities sparked by quantum simulators and their impact on non-equilibrium many-body physics. Consider the potential applications of this research in realizing experiments that enhance our understanding of far-from-equilibrium universality.