Jun 24 – 28, 2019
US/Eastern timezone
5th International Conference on the Initial Stages in High-Energy Nuclear Collisions

Off-equilibrium infrared structure of self-interacting scalar fields: Universal scaling, Vortex-antivortex superfluid dynamics and Bose-Einstein condensation

Jun 25, 2019, 3:00 PM
20m
301 (Pupin )

301

Pupin

Oral Approach to equilibrium (weak & strong coupling) Parallel: Approach to Equilibrium

Speaker

Qun Wang (University of science and technology of China)

Description

We map the infrared dynamics of a relativistic single component (N=1) interacting scalar field theory to that of nonrelativistic complex scalar fields. The Gross-Pitaevskii (GP) equation, describing the real time dynamics of single component ultracold Bose gases, is obtained at first nontrivial order in an expansion proportional to the powers of λϕ^2/m^2 where λ, ϕ and m are the coupling constant, the scalar field and the particle mass respectively. Our analytical studies are corroborated by numerical simulations of the spatial and momentum structure of overoccupied scalar fields in (2+1)-dimensions. Universal scaling of infrared modes, vortex-antivortex superfluid dynamics and the off-equilibrium formation of a Bose-Einstein condensate are observed. Our results for the universal scaling exponents are in agreement with those extracted in the numerical simulations of the GP equation. As in these simulations, we observe coarsening phase kinetics in the Bose superfluid with strongly anomalous scaling exponents relative to that of vertex resummed kinetic theory. Our relativistic field theory framework further allows one to study more closely the coupling between superfluid and normal fluid modes, specifically the turbulent momentum and spatial structure of the coupling between a quasi-particle cascade to the infrared and an energy cascade to the ultraviolet. We outline possible applications of the formalism to the dynamics of vortex-antivortex formation and to the off-equilibrium dynamics of the strongly interacting matter formed in heavy-ion collisions.

Primary authors

Raju Venugopalan (BNL) Soeren Schlichting (University of Washington) Qun Wang (University of science and technology of China)

Presentation materials