Dynamical Pion Propagation In The Functional Approach To The Charge Response.

We calculate the charge response to an electromagnetic field for a homogeneous system of nucleons and pions in the functional framework. This requires dealing with the pion propagation in the medium within the random-phase-approximation scheme. A quenching of the response is obtained in line with the experimental findings. Remarkably, the quenching takes place mainly in the isoscalar channel.