It is known that the axial anomaly (chiral anomaly, the left L- right R) shows that $U(1)_A$-axial symmetry is not a global symmetry at quantum level.
In particular, one can consider the (1) fundamental fermion and (2) adjoit fermion for QCD. The $U(1)_A$-axial symmetry is not a symmetry for both cases, but there are discrete sectors that survive as a symmetry within $U(1)_A$.
What are the remained discrete axial symmetries for (1) fundamental fermion and (2) adjoint fermion, say for a Lie group G (like SU(N))?
No comments:
Post a Comment