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arXiv · hep-th/0001097

The Intrinsic Coupling in Integrable Quantum Field Theories

J. Balog·M. Niedermaier·F. Niedermayer·A. Patrascioiu·E. Seiler·P. Weisz
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Abstract

The intrinsic 4-point coupling, defined in terms of a truncated 4-point function at zero momentum, provides a well-established measure for the interaction strength of a QFT. We show that this coupling can be computed non-perturbatively and to high accuracy from the form factors of an (integrable) QFT. The technique is illustrated and tested with the Ising model, the XY-model and the O(3) nonlinear sigma-model. The results are compared to those from high precision lattice simulations.

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J. Balog, M. Niedermaier, F. Niedermayer, A. Patrascioiu, E. Seiler, P. Weisz. 2000-01-17. The Intrinsic Coupling in Integrable Quantum Field Theories. https://doi.org/10.1016/s0550-3213(00)00277-7

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