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Title: Angular momentum conservation law in light-front quantum field theory

Abstract

We prove the Lorentz invariance of the angular momentum conservation law and the helicity sum rule for relativistic composite systems in the light-front formulation. We explicitly show that j 3 , the z -component of the angular momentum remains unchanged under Lorentz transformations generated by the light-front kinematical boost operators. The invariance of j 3 under Lorentz transformations is a feature unique to the front form. Applying the Lorentz invariance of the angular quantum number in the front form, we obtain a selection rule for the orbital angular momentum which can be used to eliminate certain interaction vertices in QED and QCD. We also generalize the selection rule to any renormalizable theory and show that there exists an upper bound on the change of orbital angular momentum in scattering processes at any fixed order in perturbation theory.

Authors:
;
Publication Date:
Research Org.:
SLAC National Accelerator Lab., Menlo Park, CA (United States)
Sponsoring Org.:
USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)
OSTI Identifier:
1362074
Report Number(s):
SLAC-PUB-16904
Journal ID: ISSN 2470-0010; PRVDAQ; arXiv:1702.01127
DOE Contract Number:
AC02-76SF00515
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review D; Journal Volume: 95; Journal Issue: 6
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; HEPTH

Citation Formats

Chiu, Kelly Yu-Ju, and Brodsky, Stanley J. Angular momentum conservation law in light-front quantum field theory. United States: N. p., 2017. Web. doi:10.1103/PhysRevD.95.065035.
Chiu, Kelly Yu-Ju, & Brodsky, Stanley J. Angular momentum conservation law in light-front quantum field theory. United States. doi:10.1103/PhysRevD.95.065035.
Chiu, Kelly Yu-Ju, and Brodsky, Stanley J. Wed . "Angular momentum conservation law in light-front quantum field theory". United States. doi:10.1103/PhysRevD.95.065035. https://www.osti.gov/servlets/purl/1362074.
@article{osti_1362074,
title = {Angular momentum conservation law in light-front quantum field theory},
author = {Chiu, Kelly Yu-Ju and Brodsky, Stanley J.},
abstractNote = {We prove the Lorentz invariance of the angular momentum conservation law and the helicity sum rule for relativistic composite systems in the light-front formulation. We explicitly show that j 3 , the z -component of the angular momentum remains unchanged under Lorentz transformations generated by the light-front kinematical boost operators. The invariance of j 3 under Lorentz transformations is a feature unique to the front form. Applying the Lorentz invariance of the angular quantum number in the front form, we obtain a selection rule for the orbital angular momentum which can be used to eliminate certain interaction vertices in QED and QCD. We also generalize the selection rule to any renormalizable theory and show that there exists an upper bound on the change of orbital angular momentum in scattering processes at any fixed order in perturbation theory.},
doi = {10.1103/PhysRevD.95.065035},
journal = {Physical Review D},
number = 6,
volume = 95,
place = {United States},
year = {Wed Mar 01 00:00:00 EST 2017},
month = {Wed Mar 01 00:00:00 EST 2017}
}
  • Cited by 3
  • We prove the Lorentz invariance of the angular momentum conservation law and the helicity sum rule for relativistic composite systems in the light-front formulation. We explicitly show that j 3, the z -component of the angular momentum remains unchanged under Lorentz transformations generated by the light-front kinematical boost operators. The invariance of j 3 under Lorentz transformations is a feature unique to the front form. Applying the Lorentz invariance of the angular quantum number in the front form, we obtain a selection rule for the orbital angular momentum which can be used to eliminate certain interaction vertices in QED andmore » QCD. We also generalize the selection rule to any renormalizable theory and show that there exists an upper bound on the change of orbital angular momentum in scattering processes at any fixed order in perturbation theory.« less
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