WG3: MACROSCOPIC SCALES – NEUTRON STARS AND THEIR LABORATORY ANALOGUES
WG3 co-leaders: Nicolas Chamel, Danai Antonopoulou
WG3 addresses the largest spatial and temporal scales relevant to superfluid dynamics, where the behaviour of the system is described by averaging over a very large number of vortices and adopting hydrodynamical approaches. This is the natural framework for the study of neutron stars, in which superfluid components coexist with normal matter and general relativistic effects play a fundamental role.
While hydrodynamical models provide the only viable description of superfluid neutron star interiors, many microscopic aspects of neutron star superfluidity remain highly uncertain. For this reason, theoretical and computational tools developed for astrophysical applications must be carefully benchmarked against laboratory systems, where parameters and initial conditions are better controlled and experimental access is possible.
WG3 therefore aims to leverage laboratory superfluids, such as helium and ultracold atomic gases, as simplified and well-characterised testbeds to validate macroscopic models of superfluid flow. These systems provide a unique opportunity to construct laboratory analogues of rotating neutron stars and to explore superfluid phenomena that are otherwise inaccessible in direct astronomical observations.
This WG will therefore focus mainly on the question:
How can laboratory results be used to constrain physics in neutron stars, and vice-versa? How can astronomical observations guide the choice of experimental setups?
In addition, WG3 will investigate how the forces acting on vortices should be modelled at hydrodynamical scales, and how the strongly inhomogeneous environment of the neutron star crust affects the global dynamics, dissipation mechanisms, and long-term evolution of the star. These aspects provide a direct link between macroscopic neutron star modelling and the scale-dependent vortex physics addressed in WG1 and WG2.
Contact: Nicolas Chamel (nicolas.chamel@ulb.be) · Danai Antonopoulou (antonopoulou.danai@gmail.com)