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.
Pasupathy et al. (Sat,) studied this question.