Quark Confinement from Different Dressed Gluon Propagators

The gap equation in quantum chromodynamics is solved by incorporating different gluon dressing functions, some of them derived from a quark–diquark potential that exhibits a conformal symmetry. By using the bare vertex and working in the Landau gauge, the quark mass function is found to have an infrared enhancement that smoothly transitions to an asymptotically free behavior at high momentum, which is consistent with the predictions of Schwinger–Dyson equations. Additionally, these quark propagators violate reflexion positivity, indicating that the gluon dressing provides clear evidence of quark confinement.