Physics Department Colloquia
Events on Friday, October 22nd, 2021
- Extremely out-of-equilibrium 1D gases
- Time: 3:30 pm
- Place: 2103 Chamberlin Hall
- Speaker: David Weiss, Penn State
- Abstract: It is notoriously hard to calculate the out-of-equilibrium dynamics of many-body quantum systems. While confining particles to one dimension sometimes simplifies dynamics, even in 1D, dynamical solutions have usually been elusive. A new approximate theory, generalized hydrodynamics (GHD), can model previously intractable dynamics. But are GHD’s approximations valid? I will describe a series of experiments with 1D Bose gases taken very far from equilibrium by, for instance, making sudden trap changes that lead them to compress 35-fold. We study the evolving distribution of rapidities, which are the momenta of the quasiparticles that emerge in these many-body systems, and which we only recently first experimentally observed for equilibrium 1D gases. These out-of-equilibrium experiments allow us to test the underlying assumptions of GHD across coupling regimes. As I will show, we find excellent agreement between our experiments and GHD theory.
- Host: Alex Levchenko