Resolution of spin crisis, and notes on the Bjorken sum rule, anomaly and constituent quark

2025/08/16 by Pasupathy, J., Singh, Janardhan P.
#FOS: Physical sciences #High Energy Physics - Experiment (hep-ex) #High Energy Physics - Phenomenology (hep-ph) #High Energy Physics - Theory (hep-th)

paper · doi:10.48550/arxiv.2508.12156

Abstract

It is shown that the widely used parton model expression for g₁ in polarized proton-lepton scattering is incorrect as it ignores gluon-quark spin entanglement. Therefore, there is no spin crisis. A brief summary of results of the theoretical evaluation of non-octet axial vector current renormalization constants and anomaly -anomaly vacuum correlator is given. It suggests that anomaly plays an important role in the transformation of current quarks to constituent quarks and chiral symmetry breaking.

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