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arXiv · hep-th/9701156

A Scaling Hypothesis for the Spectral Densities in the O(3) Nonlinear Sigma-Model

J. Balog·M. Niedermaier
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Abstract

A scaling hypothesis for the n-particle spectral densities of the O(3) nonlinear sigma-model is described. It states that for large particle numbers the n-particle spectral densities are ``self-similar'' in being basically rescaled copies of a universal shape function. This can be viewed as a 2-dimensional, but non-perturbative analogue of the KNO scaling in QCD. Promoted to a working hypothesis, it allows one to compute the two point functions at ``all'' energy or length scales. In addition, the values of two non-perturbative constants (needed for a parameter-free matching of the perturbative and the non-perturbative regime) are determined exactly.

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J. Balog, M. Niedermaier. 1997-01-28. A Scaling Hypothesis for the Spectral Densities in the O(3) Nonlinear Sigma-Model. https://doi.org/10.1103/physrevlett.78.4151

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