Luscher-corrections for 1-particle form-factors in non-diagonally scattering integrable quantum field theories

In this paper we derive from field theory a Luscher-formula, which gives the leading exponentially small in volume corrections to the 1-particle form-factors in non-diagonally scattering integrable quantum field theories. Our final formula is expressed in terms of appropriate expressions of 1- and 3-particle form-factors, and can be considered as the generalization of previous results obtained for diagonally scattering bosonic integrable quantum field theories. Since our formulas are also valid for fermions and operators with non-zero Lorentz-spin, we demonstrated our results in the Massive Thirring Model, and checked our formula against 1-loop perturbation theory finding perfect agreement.

Automated summary

In this paper, we derived a Lüscher formula from field theory, which provides the leading exponentially small corrections to the 1-particle form-factors in non-diagonally scattering integrable quantum field theories. The formula, expressed in terms of 1- and 3-particle form-factors, represents a generalization of previous results obtained for diagonally scattering bosonic integrable quantum field theories. Valid for fermions and operators with non-zero Lorentz-spin, we demonstrated the results in the Massive Thirring Model and confirmed perfect agreement with 1-loop perturbation theory.