Spontaneous Lorentz violation: the case of infrared QED

• Published in: The European physical journal. C, Particles and fields Vol. 75; no. 2; pp. 1 - 11
• Main Authors: Balachandran, A. P., Kürkçüoǧlu, S., de Queiroz, A. R., Vaidya, S.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.02.2015; Springer; Springer Nature B.V
• Subjects: Algebra; Astronomy; Astrophysics and Cosmology; Charged particles; Elementary Particles; Fermions; Hadrons; Heavy Ions; Infrared; Invariants; Measurement Science and Instrumentation; Nuclear Energy; Nuclear Physics; Photons; Physics; Physics and Astronomy; Quantum electrodynamics; Quantum Field Theories; Quantum Field Theory; Regular Article - Theoretical Physics; Sky; Spontaneous; String Theory; Vertex Operator; Lorentz Symmetry; Lorentz Invariance; Charged Particle; Coherent State
• ISSN: 1434-6044; 1434-6052
• DOI: 10.1140/epjc/s10052-015-3305-0

It is by now clear that the infrared sector of quantum electrodynamics (QED) has an intriguingly complex structure. Based on earlier pioneering work on this subject, two of us recently proposed a simple modification of QED by constructing a generalization of the U ( 1 ) charge group of QED to the “Sky” group incorporating the well-known spontaneous Lorentz violation due to infrared photons, but still compatible in particular with locality (Balachandran and Vaidya, Eur Phys J Plus 128:118, 2013 ). It was shown that the “Sky” group is generated by the algebra of angle-dependent charges and a study of its superselection sectors has revealed a manifest description of spontaneous breaking of the Lorentz symmetry. We further elaborate this approach here and investigate in some detail the properties of charged particles dressed by the infrared photons. We find that Lorentz violation due to soft photons may be manifestly codified in an angle-dependent fermion mass, modifying therefore the fermion dispersion relations. The fact that the masses of the charged particles are not Lorentz invariant affects their spin content, and time dilation formulas for decays should also get corrections.