Revisiting the flux tube spectrum of 3d SU(2) lattice gauge theory

We perform a high-precision measurement of the spectrum of the flux tube in three-dimensional SU(2) gauge theory at multiple lattice spacings. We compare the results at large q (q) over bar over bar separations R to the spectrum predicted by the effective string theory, including the leading-order boundary term with a nonuniversal coefficient. We find qualitative agreement with the predictions from the leading-order Nambu-Goto string theory down to small values of R, while, at the same time, observing the predicted splitting of the second excited state due to the boundary term. On fine lattices and at large R, we observe slight deviations from the EST predictions for the first excited state.

Automated summary

In this study, a high-precision measurement of the spectrum of the flux tube in three-dimensional SU(2) gauge theory was conducted at multiple lattice spacings. Comparisons were made with predictions from effective string theory, showing qualitative agreement with Nambu-Goto string theory predictions at small R values but slight deviations for the first excited state.