Anomalies in Ward Identities
In certain generalized Ward-identities perturbation theory can lead to deviations from the relations, derived by canonical field theory. Such a modification caused by the fermion triangle graph in the axial-photon-vertex, was discussed in several papers during the last year. We try to show, also by means of other simple field theoretical models, that the problem of such “anomalies” is by no means solved, since the interpretation of the mathematical equations in terms of experimentally measurable (“renormalized”) quantities is still very arbitrary. E.g. sometimes only by abolishing the normal-ordering prescription “anomalies” become “normal” tadpole-contributions.
KeywordsWard Identity Counter Term Photon Mass Axial Vector Current Equal Time Commutator
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