Two-point Correlation Function in Integrable QFT with Anti-Crossing Symmetry

TL;DR

This paper computes the two-point correlation function in a specific integrable quantum field theory, demonstrating a precise match between ultraviolet perturbative and spectral representations, illustrating the interpolation between IR and UV behaviors.

Contribution

It provides an explicit calculation of the stress-energy tensor correlation function in a non-unitary integrable QFT, highlighting the convergence of different computational approaches.

Findings

Spectral and perturbative methods converge rapidly.

Explicit interpolation between IR and UV regimes.

Accurate correlation function computation in a non-unitary model.

Abstract

The two-point correlation function of the stress-energy tensor for the $\Phi_{1,3}$ massive deformation of the non-unitary model ${\cal M}_{3,5}$ is computed. We compare the ultraviolet CFT perturbative expansion of this correlation function with its spectral representation given by a summation over matrix elements of the intermediate asymptotic massive particles. The fast rate of convergence of both approaches provides an explicit example of an accurate interpolation between the infrared and ultraviolet behaviours of a Quantum Field Theory.