Propagation of neutral mesons in asymmetric nuclear matter

We calculate dispersion relations and propagators for the $\sigma$, $\omega$, $\rho$ and $\delta$ mesons in relativistic nuclear matter with a proton-neutron asymmetry. In addition to the $\sigma$-$\omega$ and $\delta$-$\rho$ mixings already present in symmetric matter, mixing occur between all components of the $\sigma$-$\omega$-$\delta$-$\rho$ system when the proton fraction differs from 1/2.