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arXiv · 1509.01414

Manifestly gauge-covariant representation of scalar and fermion propagators

Adam Latosiński
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Abstract

A new way to write the massive scalar and fermion propagators on a background of a weak gauge field is presented. They are written in a form that is manifestly gauge-covariant up to several additional terms that can be written as boundary terms in momentum space. These additional terms violate Ward-Takahashi identities and need to be renormalized by appropriate counterterms if the complete theory is to be gauge-covariant. This form makes it possible to calculate many amplitudes in a manifestly gauge-covariant way (at the same time reducing the number of Feynman diagrams). It also allows to express some counterterms in a way independent of the regularization scheme and provides an easy way to derive the anomalous term affecting the chiral current conservation.

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Adam Latosiński. 2015-09-04. Manifestly gauge-covariant representation of scalar and fermion propagators. https://doi.org/10.1103/physrevd.93.025031

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