In this problem we assume that the photon mass is m > 0. We take a conducting sphere of radius R and put a charge of Q on it. Some fraction of the charge will then reside at the surface and a fraction will move into the bulk. Evaluate the volume charge density in the bulk. I was shocked to learn in another thread that some people believe that the fact that there are no charges inside a conductor has nothing to do with Coulomb's law (apart from the mere fact that it leads to a repulsion between like charges). So, I invented this problem, solved it, and because it turned out to be quite easy, posted it here. B.t.w., what is even easier is to simply see that not all of the charge can reside at the surface.