Electrodynamics of massless charged particles
Abstract
We derive the classical dynamics of massless charged particles in a rigorous way from first principles. Since due to ultraviolet divergences this dynamics does not follow from an action principle, we rely on (a) Maxwell’s equations, (b) Lorentz and reparameterizationinvariance, and (c) local conservation of energy and momentum. Despite the presence of pronounced singularities of the electromagnetic field along Diraclike strings, we give a constructive proof of the existence of a unique distributionvalued energymomentum tensor. Its conservation requires the particles to obey standard Lorentz equations and they experience, hence, no radiation reaction. Correspondingly, the dynamics of interacting classical massless charged particles can be consistently defined, although they do not emit bremsstrahlung end experience no selfinteraction.
 Authors:
 Dipartimento di Fisica e Astronomia, Università degli Studi di Padova, Padova, Italy and INFN, Sezione di Padova, Via F. Marzolo, 8, 35131 Padova (Italy)
 Publication Date:
 OSTI Identifier:
 22403109
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Journal of Mathematical Physics; Journal Volume: 56; Journal Issue: 2; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; BREMSSTRAHLUNG; CHARGED PARTICLES; ELECTRODYNAMICS; ELECTROMAGNETIC FIELDS; ENERGYMOMENTUM TENSOR; PARTICLES; ULTRAVIOLET DIVERGENCES
Citation Formats
Lechner, Kurt, Email: kurt.lechner@pd.infn.it. Electrodynamics of massless charged particles. United States: N. p., 2015.
Web. doi:10.1063/1.4906813.
Lechner, Kurt, Email: kurt.lechner@pd.infn.it. Electrodynamics of massless charged particles. United States. doi:10.1063/1.4906813.
Lechner, Kurt, Email: kurt.lechner@pd.infn.it. 2015.
"Electrodynamics of massless charged particles". United States.
doi:10.1063/1.4906813.
@article{osti_22403109,
title = {Electrodynamics of massless charged particles},
author = {Lechner, Kurt, Email: kurt.lechner@pd.infn.it},
abstractNote = {We derive the classical dynamics of massless charged particles in a rigorous way from first principles. Since due to ultraviolet divergences this dynamics does not follow from an action principle, we rely on (a) Maxwell’s equations, (b) Lorentz and reparameterizationinvariance, and (c) local conservation of energy and momentum. Despite the presence of pronounced singularities of the electromagnetic field along Diraclike strings, we give a constructive proof of the existence of a unique distributionvalued energymomentum tensor. Its conservation requires the particles to obey standard Lorentz equations and they experience, hence, no radiation reaction. Correspondingly, the dynamics of interacting classical massless charged particles can be consistently defined, although they do not emit bremsstrahlung end experience no selfinteraction.},
doi = {10.1063/1.4906813},
journal = {Journal of Mathematical Physics},
number = 2,
volume = 56,
place = {United States},
year = 2015,
month = 2
}

The infrared problem associated with massless charged particles is discussed at a nonperturbative level, extending previous results. It is shown that the validity of the relativistic spectral conditions and the existence of asymptotic photons forbid the existence of massless charged particles. The same conclusion is proved for massive charged particles in 2+1 dimensions. copyright 1986 Academic Press, Inc.

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