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arXiv · hep-th/9202020

Thermodynamic Bethe Ansatz for G_k x G_l / G_{k+l} Coset Models Perturbed by Their ϕ_{1,1,Adj} Operator

F. Ravanini
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Abstract

We propose a Thermodynamic Bethe Ansatz (TBA) for G_k x G_l / G_{k+l} conformal coset models (G any simply-laced Lie algebra) perturbed by their operator ϕ_{1,1,Adj}. An interesting adjacency structure appears and can be depicted in a sort of ``product'' of Dynkin diagrams of G and A_{k+l-1}. UV and IR limits are computed and reproduce the expected values for the central charges. For k->\infty, l fixed we obtain the TBA of the G_l WZW model perturbed by J_a\bar{J}_a, and for k,l->\infty, k-l fixed, that of Principal Chiral model with WZ term at level k-l.

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F. Ravanini. 1992-02-06. Thermodynamic Bethe Ansatz for G_k x G_l / G_{k+l} Coset Models Perturbed by Their ϕ_{1,1,Adj} Operator. https://doi.org/10.1016/0370-2693(92)90481-i

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