Chemical potential dependence of pi and rho properties
  Using a confining, Dyson-Schwinger equation model of QCD at finite temperature (T) and chemical potential (mu) we study the behaviour of <q-bar q>, m_pi, f_pi and the masses of the rho- and phi-mesons. For each of these quantities there is a necessary anticorrelation between its response to T and its response to mu. (-<q-bar q>) and f_pi decrease with T and increase with mu; m_pi is almost insensitive to T and mu until very near the border of the confinement domain; and the mass of the longitudinal component of the vector mesons increases with T and decreases with mu. At T=0, the rho-meson mass is reduced by approximately 15% at nuclear matter density. These results are a consequence of the necessary momentum-dependence of the dressed-quark self-energy. 
P. Maris, C. D. Roberts and S. Schmidt