We report a first case study of the phase diagram of 2+1 flavor strongly
interacting matter in β−equilibrium, using the
Polyakov−Nambu−Jona-Lasinio model. Physical characteristics of relevant
thermodynamic observables have been discussed. A comparative analysis with the
corresponding observables in the Nambu-Jona-Lasinio model is presented. We find
distinct differences between the models in terms of a number of thermodynamic
quantities like the speed of sound, specific heat, various number densities as
well as entropy. The present study is expected to give us a better insight into
the role that the superdense matter created in heavy ion collision experiments
play in our understanding of the properties of matter inside the core of
supermassive stars in the Universe