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Propagators with the Mandelstam-Leibbrandt Prescription in the Light-Cone Gauge

Ashok Das·J. Frenkel
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Abstract

We show that the Feynman propagator in the light-cone gauge with the Mandelstam-Leibbrandt prescription has a logarithmic growth for large $\tilde{n}\cdot x$ which is related to the presence of a residual gauge invariance. Furthermore, we show that the retarded propagator for the $\tilde{n}\cdot A$ component of the gauge field develops a coordinate dependent mass which is inversely proportional to the magnitude of the transverse coordinate. We argue that this unphysical behavior may be eliminated by fixing the residual gauge degrees of freedom.

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Ashok Das, J. Frenkel. 2005-03-28. Propagators with the Mandelstam-Leibbrandt Prescription in the Light-Cone Gauge. https://doi.org/10.1103/physrevd.71.087701

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