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Instanton-Sphaleron transition in the d = 2 Abelian-Higgs model on a Circle

D. K. Park·H. J. W. Müller-Kirsten·J. -Q. Liang·A. V. Shurgaia
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Abstract

The transition from the instanton-dominated quantum regime to the sphaleron-dominated classical regime is studied in the $d=2$ abelian-Higgs model when the spatial coordinate is compactified to $S^1$. Contrary to the noncompactified case, this model allows both sharp first-order and smooth second-order transitions depending on the size of the circle. This finding may make the model a useful toy model for the analysis of baryon number violating processes. Since the model can to a large extent be treated analytically, it can also serve as a transparent prototype for the application of our method to more complicated cases, such as those in higher dimensions.

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D. K. Park, H. J. W. Müller-Kirsten, J. -Q. Liang, A. V. Shurgaia. 2001-05-29. Instanton-Sphaleron transition in the d = 2 Abelian-Higgs model on a Circle. https://doi.org/10.1142/s0217751x01005055

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