Goldstone mode of chiral symmetry in quantum chromodynamics

Abstract

We examine the Dyson qeuation for the quark propagator and the Ward identity for the quark-gluon vertex function in the framework of the gauge technique with the object of investigating broken chiral symmetry in quantum chromodynamics with massless quarks. We find that the chiral-symmetric Wigner-Weyl solution is realized only when the transverse part of the quark-gluon vertex is suppressed; its presence necessarily requires the spontaneous breakdown of chiral symmetry.