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The Field Theory of the q->4+ Potts Model

G. Delfino·John Cardy
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Abstract

The q-state Potts model in two dimensions exhibits a first-order transition for q>4. As q->4+ the correlation length at this transition diverges. We argue that this limit defines a massive integrable quantum field theory whose lowest excitations are kinks connecting 4+1 degenerate ground states. We construct the S-matrix of this theory and the two-particle form factors, and hence estimate a number of universal amplitude ratios. These are in very good agreement with the results of extrapolated series in q^(-1/2) as well as Monte Carlo results for q=5.

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G. Delfino, John Cardy. 2000-02-15. The Field Theory of the q->4+ Potts Model. https://doi.org/10.1016/s0370-2693(00)00548-7

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