  At finite temperature, chiral quark models do not incorporate large gauge
invariance which implies genuinely non-perturbative finite temperature gluonic
degrees of freedom. Motivated by this observation, we describe how the coupling
of the Polyakov loop as an independent degree of freedom to quarks not only
accounts for large gauge invariance, but also allows to establish in a
dynamical way the interaction between composite hadronic states such as
Goldstone bosons to finite temperature non-perturbative gluons in a medium
which can undergo a confinement-deconfinement phase transition.

High Energy Physics - Phenomenology