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arXiv · hep-th/9812023

On the trace identity in a model with broken symmetry

Daniel H. T. Franco
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Abstract

Considering the simple chiral fermion meson model when the chiral symmetry is explicitly broken, we show the validity of a trace identity -- to all orders of perturbation theory -- playing the role of a Callan-Symanzik equation and which allows us to identify directly the breaking of dilatations with the trace of the energy-momentum tensor. More precisely, by coupling the quantum field theory considered to a classical curved space background, represented by the non-propagating external vielbein field, we can express the conservation of the energy-momentum tensor through the Ward identity which characterizes the invariance of the theory under the diffeomorphisms. Our ``Callan-Symanzik equation'' then is the anomalous Ward identity for the trace of the energy-momentum tensor, the so-called ``trace identity''.

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Daniel H. T. Franco. 1999-03-25. On the trace identity in a model with broken symmetry. https://doi.org/10.1103/physrevd.59.125017

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