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arXiv · hep-th/9604161

Perturbative versus Non-perturbative QFT -- Lessons from the O(3) NLS Model

J. Balog·M. Niedermaier·T. Hauer
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Abstract

The two-point functions of the energy-momentum tensor and the Noether current are used to probe the O(3) nonlinear sigma model in an energy range below 10^4 in units of the mass gap $m$. We argue that the form factor approach, with the form factor series trunctated at the 6-particle level, provides an almost exact solution of the model in this energy range. The onset of the (2-loop) perturbative regime is found to occur only at energies around $100m$.

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J. Balog, M. Niedermaier, T. Hauer. 1996-12-04. Perturbative versus Non-perturbative QFT -- Lessons from the O(3) NLS Model. https://doi.org/10.1016/0370-2693(96)00906-9

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