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Space-like energy momentum in quantum electrodynamics

Dan Solomon
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Abstract

A common assumption in quantum field theory is that the energy-momentum 4-vector of any quantum state must be time-like. However it has been recently shown [4] that this is not the case for a Dirac-Maxwell field in the coulomb gauge. Here we will present a proof that is simpler then the proof of Ref. [4] that there must exist quantum states which are space-like for a Dirac-Maxwell field in the coulomb gauge.

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Dan Solomon. 2007-03-27. Space-like energy momentum in quantum electrodynamics. https://arxiv.org/abs/quant-ph/0703257

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