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arXiv · hep-th/9306131

On the Physical Propagators of QED

Martin Lavelle·David McMullan
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Abstract

The true variables in QED are the transverse photon components and Dirac's physical electron, constructed out of the fermionic field and the longitudinal components of the photon. We calculate the propagators in terms of these variables to one loop and demonstrate their gauge invariance. The physical electron propagator is shown not to suffer from infrared divergences in any gauge. In general, all physical Green's functions are gauge invariant and infrared-finite.

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Martin Lavelle, David McMullan. 1993-06-25. On the Physical Propagators of QED. https://doi.org/10.1016/0370-2693(93)90512-g

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