2021/01/06 by Michael J. Landry, Landry, Michael J. · 1 citation
Physics and Astronomy · #Advanced Thermodynamics and Statistical Mechanics #FOS: Physical sciences #General Relativity and Quantum Cosmology (gr-qc) #High Energy Physics - Theory (hep-th) #Nuclear Theory (nucl-th) #Other Condensed Matter (cond-mat.other) #Quantum Mechanics and Applications #Quantum, superfluid, helium dynamics
paper · pdf · doi:10.48550/arxiv.2101.02210
openalex publication_date 2021/01/06 · openalex created_date 2022/07/25 · openalex updated_date 2026/07/28
We investigate the role of higher-form symmetries in non-equilibrium systems from the perspective of effective actions defined on the Schwinger-Keldysh contour. To aid our investigation, we extend the coset construction to account for p-form symmetries at zero and finite temperature. Additionally we investigate how, out of equilibrium, symmetries of the action need not lead to meaningful conserved currents at the level of the equations of motion. For reasons that will become apparent, we term symmetries with conserved currents Stückelberg symmetries and those without meaningful conserved currents non-Stückelberg symmetries (NSS). Ordinarily any action constructed exclusively from building-blocks furnished by the coset construction will have Stückelberg symmetries associated with each symmetry generator. To expand the set of systems describable by the coset construction, we devise a method by which NSS generators can be included as well. While 0-form NSS are quite common in non-equilibrium effective actions, the introduction of p-form NSS is novel. We use these p-form NSS to investigate spontaneous symmetry breaking of p-form symmetries. We find that in non-equilibrium systems, whether or not a symmetry appears spontaneously broken can depend on the time-scale over which the system is observed. Finally, using our new coset construction, we formulate actions for a number of systems including chemically reacting fluids, Yang-Mills theory, Chern-Simons theory, magnetohydrodynamic systems, and dual superfluid and solid theories.