Dual Interpretations of Pion Clouds at RHIC
  A gauge theory of pions interacting with rho-mesons at elevated temperatures is used to calculate the pressure in a hot pion gas. No reference is made to the pion's status as a QCD Goldstone boson. The role of the pion is merely that of a carrier of an SU(2) symmetry, gauged to create a vector-meson interaction, the rho playing the role of the interacting vector particle. The results are in rough agreement with much more elaborate calculations, both of the purely hadronic variety, and those that invoke quark-gluon degrees of freedom. The quark-gluon and purely hadronic calculations seemingly lead to very similar predictions which are in accord with receent data from RHIC. The results motivate the question as to whether the two descriptions are dual to each other in the sense of being alternate models, each sufficient to explain the observed data. 
Jack L. Uretsky