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Bethe Ansatz for a Quantum Supercoset Sigma Model

Nelia Mann·Joe Polchinski
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Abstract

We study an integrable conformal OSp(2m + 2|2m) supercoset model as an analog to the AdS_5 X S^5 superstring world-sheet theory. Using the known S-matrix for this system, we obtain integral equations for states of large particle density in an SU(2) sector, which are exact in the sigma model coupling constant. As a check, we derive as a limit the general classical Bethe equation of Kazakov, Marshakov, Minahan, and Zarembo. There are two distinct quantum expansions around the well-studied classical limit, the lambda^{-1/2} effects and the 1/J effects. Our approach captures the first type, but not the second.

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Nelia Mann, Joe Polchinski. 2005-09-09. Bethe Ansatz for a Quantum Supercoset Sigma Model. https://doi.org/10.1103/physrevd.72.086002

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