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arXiv · hep-th/9409142

The Exact Mass-Gap of the Supersymmetric CP^{n-1} Sigam Model

Jonathan M. Evans·Timothy J. Hollowood
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Abstract

A formula for the mass-gap of the supersymmetric $\CP^{n-1}$ sigma model ($n > 1$) in two dimensions is derived: $m/Λ_{\overline{\rm MS}}=\sin(πΔ)/(πΔ)$ where $Δ=1/n$ and $m$ is the mass of the fundamental particle multiplet. This result is obtained by comparing two expressions for the free-energy density in the presence of a coupling to a conserved charge; one expression is computed from the exact S-matrix of Köberle and Kurak via the thermodynamic Bethe ansatz and the other is computed using conventional perturbation theory. These calculations provide a stringent test of the S-matrix, showing that it correctly reproduces the universal part of the beta-function and resolving the problem of CDD ambiguities.

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Jonathan M. Evans, Timothy J. Hollowood. 1994-09-23. The Exact Mass-Gap of the Supersymmetric CP^{n-1} Sigam Model. https://doi.org/10.1016/0370-2693(94)01478-u

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