MS Seminar (Mathematics - String Theory)

Speaker: Susanne Reffert (University of Bern)
Title: The large charge expansion for relativistic and non-relativistic physics
Date (JST): Tue, Jan 06, 2026, 13:30 - 15:00
Place: Seminar Room A
Abstract:
The large-charge expansion is a powerful approach for analytically accessing strongly-coupled models at or near criticality. We focus on a sector of fixed and large global charge where it is possible to express observables as an expansion in inverse powers of the charge.
I will first introduce the approach using the simplest relativistic case, namely the O(2) model. Then I will discuss the large-charge expansion of non-relativistic models with applications to ultracold Fermi gases and nuclear physics.