Chiral symmetry in strongly interacting matter

Abstract

This is a brief summary of topics that were presented as lectures within the programme _s15New Frontiers in QCD 2010_s15 at the Yukawa Institute of Theoretical Physics in Kyoto. The basic subject is phases and symmetry breaking patterns as they emerge from the approximate chiral symmetry of QCD. Part I focuses on the QCD interface with nuclear physics via chiral effective field theory. This includes nuclear thermodynamics and, in particular, constraints for compressed and hot baryonic matter provided by the density and temperature dependence of the chiral condensate. Part II explores aspects of the QCD phase diagram using a non-local improved version of the Polyakov - Nambu - Jona-Lasinio (PNJL) model. A prominent feature of such an approach is the occurence of a dynamical entanglement between chiral and deconfinement crossover transitions. Comparisons with available results from lattice QCD thermodynamics will be made.