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Quantum Electrodynamics at Large Distances II: Nature of the Dominant Singularities

Henry P. Stapp·Takahiro Kawai
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Abstract

Accurate calculations of macroscopic and mesoscopic properties in quantum electrodynamics require careful treatment of infrared divergences: standard treatments introduce spurious large-distances effects. A method for computing these properties was developed in a companion paper. That method depends upon a result obtained here about the nature of the singularities that produce the dominant large-distance behaviour. If all particles in a quantum field theory have non-zero mass then the Landau-Nakanishi diagrams give strong conditions on the singularities of the scattering functions. These conditions are severely weakened in quantum electrodynamics by effects of points where photon momenta vanish. A new kind of Landau-Nakanishi diagram is developed here. It is geared specifically to the pole-decomposition functions that dominate the macroscopic behaviour in quantum electrodynamics, and leads to strong results for these functions at points where photon momenta vanish.

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Henry P. Stapp, Takahiro Kawai. 1995-11-21. Quantum Electrodynamics at Large Distances II: Nature of the Dominant Singularities. https://doi.org/10.1103/physrevd.52.2505

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