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arXiv · 1609.00746

Revisiting the equivalence of light-front and covariant QED in the light-cone gauge

Luca Mantovani·Barbara Pasquini·Xiaonu Xiong·Alessandro Bacchetta
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Abstract

We discuss the equivalence between light-front time-ordered-perturbation theory and covariant quantum field theory in light-front quantization, in the case of quantum electrodynamics at one-loop level. In particular, we review the one-loop calculation of the vertex correction, fermion self-energy and vacuum polarization. We apply the procedure of integration by residue over the light-front energy in the loop to show how the perturbative expansion in covariant terms can be reduced to a sum of propagating and instantaneous diagrams of light-front time-ordered perturbation theory. The detailed proof of equivalence between the two formulations of the theory resolves the controversial question on which form should be used for the gauge-field propagator in the light-cone gauge in the covariant approach.

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Luca Mantovani, Barbara Pasquini, Xiaonu Xiong, Alessandro Bacchetta. 2016-09-02. Revisiting the equivalence of light-front and covariant QED in the light-cone gauge. https://doi.org/10.1103/physrevd.94.116005

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