Playing with QCD I: effective field theories. Third lecture

One can construct useful effective models to describe the deconfining transition using the Polyakov loop as the building block. This procedure was generalized to a matrix model approach, including fermions as a background field (not discussed here). The chiral transition can be described using the chiral condensate as the order parameter. Nonzero (even if small) quark masses bring non-trivial consequences to the phase structure of QCD. Are deconfinement and chiral transition closely related? Do they happen at the same T? Several effective approaches available, but physics still unclear. (author)