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Radiating and Non-Radiating Current Distributions in Quantum Electrodynamics

G. Castellani·S. Sivasubramanian·A. Widom·Y. N. Srivastava
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Abstract

The notion of ``radiating'' and ``non-radiating'' current sources in classical electrodynamics plays an important role in calculations of direct and inverse electromagnetic scattering problems. Such a decomposition of the current is central for the notion of localized non-radiating electromagnetic modes. A completely quantum electrodynamic view is explored in this work. Photon emission and absorption current sources are classified as being either radiating or non-radiating. This quantum classification corresponds, respectively and exactly, to the notion of ``real'' and ``virtual'' photon processes. Causal properties of both real and virtual electromagnetic fields are discussed.

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G. Castellani, S. Sivasubramanian, A. Widom, Y. N. Srivastava. 2003-06-26. Radiating and Non-Radiating Current Distributions in Quantum Electrodynamics. https://arxiv.org/abs/quant-ph/0306185

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