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Perturbation theory for the two-dimensional abelian Higgs model in the unitary gauge

Enno E. Scholz·Gernot Münster
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Abstract

In the unitary gauge the unphysical degrees of freedom of spontaneously broken gauge theories are eliminated. The Feynman rules are simpler than in other gauges, but it is non-renormalizable by the rules of power counting. On the other hand, it is formally equal to the limit $ξ\to 0$ of the renormalizable R$_ξ$-gauge. We consider perturbation theory to one-loop order in the R$_ξ$-gauge and in the unitary gauge for the case of the two-dimensional abelian Higgs model. An apparent conflict between the unitary gauge and the limit $ξ\to 0$ of the R$_ξ$-gauge is resolved, and it is demonstrated that results for physical quantities can be obtained in the unitary gauge.

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Enno E. Scholz, Gernot Münster. 2003-11-04. Perturbation theory for the two-dimensional abelian Higgs model in the unitary gauge. https://doi.org/10.1140/epjc%2Fs2003-01327-9

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