WG2: INTERMEDIATE SCALES – SUPERFLUID TURBULENCE
WG2 co-leaders: Emil Varga, Luca Galantucci
WG2 focuses on the intermediate scales of superfluid dynamics, where the internal structure of individual vortex cores can be neglected, but collective interactions between a large number of vortices become the dominant physical mechanism shaping the flow.
In this regime, vortices can be treated as effectively massless filaments, allowing for the use of vortex filament (VF) methods to model complex vortex tangles and large-scale flow patterns. These approaches provide a powerful theoretical and numerical framework to describe experiments involving many interacting vortices, where superfluid turbulence naturally emerges.
Such turbulent regimes are routinely observed in experiments with superfluid helium-3 and helium-4 in rotating containers, where large vortex ensembles are generated and driven far from equilibrium. Similar phenomena also arise in three-dimensional Bose–Einstein condensates, and may play a crucial role in neutron star interiors following large-scale dynamical events such as glitches or rotational instabilities.
By comparing different physical platforms, WG2 aims to identify universal features of quantum turbulence as well as system-specific effects arising from differences between bosonic and fermionic superfluids, dissipation mechanisms, and external driving.
This WG will therefore focus mainly on the question:
How does turbulence emerge and decay in different superfluid systems?
In addition, WG2 will investigate how turbulent dynamics are linked to the forces driving vortex motion, and how these processes are modified by motion through inhomogeneous media, such as externally imposed density variations, pinning landscapes, or phase boundaries. These aspects directly connect WG2 to the broader Action questions concerning vortex forces and inhomogeneity effects across different scales.
Contact: Emil Varga (emil.varga@matfyz.cuni.cz) · Luca Galantucci (luca.galantucci@cnr.it)