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arXiv · hep-th/9402084

The exact mass-gaps of the principal chiral models

T. J. Hollowood
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Abstract

An exact expression for the mass-gap, the ratio of the physical particle mass to the $Λ$-parameter, is found for the principal chiral sigma models associated to all the classical Lie algebras. The calculation is based on a comparison of the free-energy in the presence of a source coupling to a conserved charge of the theory computed in two ways: via the thermodynamic Bethe Ansatz from the exact scattering matrix and directly in perturbation theory. The calculation provides a non-trivial test of the form of the exact scattering matrix.

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T. J. Hollowood. 1994-02-15. The exact mass-gaps of the principal chiral models. https://doi.org/10.1016/0370-2693(94)91089-8

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