Gauge invariance and hadron structure

1998/02/18 by Xiang-Song Chen, Fan Wang, Chen, Xiang-Song +1
Physics and Astronomy · #FOS: Physical sciences #High Energy Physics - Phenomenology (hep-ph) #hep-ph

paper · pdf · doi:10.48550/arxiv.hep-ph/9802346

This revised version gives a complete, comprehensive proof of our conclusion, and explains why the specific calculations of Hoodbhoy, Ji and Lu (hep-ph/9808305) do not necessarily contradict our theorem

arxiv created 1998/09/19 · arxiv updated 2009/11/30

Abstract

We prove that the \em gauge dependent gluon spin, gluon and quark orbital angular momenta operators have \em gauge invariant expectation values on hadron states with \em definite momentum and polarization, therefore the conventional decomposition of nucleon spin into contributions from the spin and orbital angular momentum of quark and gluon is \em gauge independent. Similar conclusions apply to the \em gauge dependent quark momentum and kinetic energy operators, and accordingly nucleon momentum and mass structures.

Related

• The application of gauge invariance and canonical quantization to the internal structure of gauge field systems
• Quantum Version of Gauge Invariance and Nucleon Internal Structure
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• Poincaré subalgebra and gauge invariance in nucleon structure
• Unexpected equality of the quark and gluon Belinfante angular momentum and Canonical angular momentum in the light-cone gauge A⁺=0, in a spin 1/2 nucleon