The large charge expansion

The large-charge approach consists in studying conformal field theories in sectors of fixed and large global charge. This allows performing a perturbative expansion of a generically strongly-coupled theory with the inverse charge acting as a controlling parameter. In this talk, I will present the basic idea of the large quantum number expansion using the simplest example of the 3D O(2) model at the Wilson-Fisher fixed point at large global charge and then extend its treatment to the O(2N) vector model. New lattice results confirm our predictions to high accuracy. I will further show that the large-charge expansion can also be successfully applied to non-relativistic CFTs.

Tuesday, 7th of May 2019, 14:30, sala Wataghin