Thermodynamical consistency of the EOS of finite-size hadrons and the quark-hadron phase transition

The importance of the thermodynamical consistency of the Van der Waals type equation of state (EOS) of strongly interacting matter consisting of baryons, mesons and their antiparticles is discussed. It is shown that the earlier proposed thermodynamically consistent model of Rischke et al. is only mathematically justified but seems physically unsound. The resulting discrepancy, which increases with increasing number of components in the system, and its possible effects on the critical parameters of the quark-hadron phase transition are discussed. The present model incorporates the effect of the excluded volume in a more realistic manner providing an EOS which is thermodynamically consistent and physically justifiable.