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arXiv · 1605.07836

Phase structure of the $O(2)$ ghost model with higher-order gradient term

Z. Péli·S. Nagy·K. Sailer
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Abstract

The phase structure and the infrared behaviour of the Euclidean 3-dimensional $O(2)$ symmetric ghost scalar field model with higher-order derivative term has been investigated in Wegner and Houghton's renormalization group framework. The symmetric phase in which no ghost condensation occurs and the phase with restored symmetry but with a transient presence of a ghost condensate have been identified. Finiteness of the correlation length at the phase boundary hints to a phase transition of first order. The results are compared with those for the ordinary $O(2)$ symmetric scalar field model.

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Z. Péli, S. Nagy, K. Sailer. 2016-05-25. Phase structure of the $O(2)$ ghost model with higher-order gradient term. https://doi.org/10.1103/physrevd.94.065021

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