Speaker
Description
Quantised vortices and magnetic flux tubes are expected to govern key aspects of neutron star dynamics, but their bulk behaviour is difficult to isolate numerically due to boundary effects in finite domains. Despite an unavoidable topological obstruction, it is possible to study topological defects in periodic domains by relaxing the requirement of periodicity for the condensate's phase. Building on this idea, I will present a Gross-Pitaevskii framework with quasi-periodic boundary conditions for vortex dynamics at finite net vorticity (and its related public simulation code, GINTONIC), and a two-component Ginzburg-Landau model for coupled neutron and proton condensates. Together, these models provide a way to study how topological defects interact while avoiding possible spurious effects associated with hard walls or confining potentials. In particular, I will discuss how this framework can be used to investigate type-1.5 superconductivity in neutron stars, the formation of flux-tube bouquets around vortices, and the pinning of vortices to flux tubes.
GitHub code repository: GINTONIC - Gross-Pitaevskii Integrator on a Torus with non-zero Vorticity, https://github.com/Magistrelli/gintonic
Based on: Dynamics of quantized vortices under quasi-periodic boundary conditions, https://arxiv.org/abs/2509.15298