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Quantum Effects in Softly Broken Gauge Theories in Curved Space-Times

I. L. Buchbinder·G. de Berredo-Peixoto·I. L. Shapiro
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Abstract

The soft breaking of gauge or other symmetries is the typical Quantum Field Theory phenomenon. In many cases one can apply the St$\ddot{\rm u}$ckelberg procedure, which means introducing some additional field or fields and restore the gauge symmetry. The original softly broken theory corresponds to a particular choice of the gauge fixing condition. In this paper we use this scheme for performing quantum calculations for some softly broken gauge theories in an arbitrary curved space-time. The following examples are treated in details: Proca field, massive QED and massive torsion coupled to fermion. Furthermore we present a qualitative discussions of the discontinuity of quantum effects in the massive spin-2 field theory, paying special attention to the similarity and differences with the massless limit in the spin-1 case.

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I. L. Buchbinder, G. de Berredo-Peixoto, I. L. Shapiro. 2007-03-21. Quantum Effects in Softly Broken Gauge Theories in Curved Space-Times. https://doi.org/10.1016/j.physletb.2007.04.039

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