Revealing Universal Physics in Quantum Dynamics.

New experiments using ultra-cold atomic gases reveal a universality in how quantum systems composed of many particles change over time following a large influx of energy that throws the system out of equilibrium. Penn State physicists showed that these gases immediately respond, "evolving" with features that are common to all "many-body" quantum systems thrown out of equilibrium in this way. The experiment and theory together provide a model example of hydrodynamization, which happens so fast that the underlying understanding in terms of quasi-particles can be applied to any many-body quantum system to which a very large amount of energy is added.