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arXiv · 1007.5182

Phase Structure and Compactness

I. Nandori·S. Nagy·K. Sailer·A. Trombettoni
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Abstract

In order to study the influence of compactness on low-energy properties, we compare the phase structures of the compact and non-compact two-dimensional multi-frequency sine-Gordon models. It is shown that the high-energy scaling of the compact and non-compact models coincides, but their low-energy behaviors differ. The critical frequency $β^2 = 8π$ at which the sine-Gordon model undergoes a topological phase transition is found to be unaffected by the compactness of the field since it is determined by high-energy scaling laws. However, the compact two-frequency sine-Gordon model has first and second order phase transitions determined by the low-energy scaling: we show that these are absent in the non-compact model.

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I. Nandori, S. Nagy, K. Sailer, A. Trombettoni. 2010-09-15. Phase Structure and Compactness. https://doi.org/10.1007/jhep09(2010)069

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