Energy decay of electromagnetic systems with memory

We consider a linear evolution problem with memory arising in the theory of hereditary
electromagnetism. Under general assumptions on the memory kernel, all single trajectories
are proved to decay to zero, but the decay rate is not uniform in dependence of
the initial data, so that the system is not exponentially stable. Nonetheless, if the kernel
is rapidly fading and close to the Dirac mass at zero, then the solutions are close to
exponentially stable trajectories.