  We investigate the energy loss of heavy quarks in the gas, liquid and solid
phase of a classical quark-gluon plasma (cQGP) using molecular dynamics
simulations. The model consists of massive quarks and gluons interacting as a
classical non-relativistic colored Coulomb gas. We show that the electric force
decorrelates on a short time scale causing the energy loss to be mostly
diffusive and langevin-like in the cQGP. We find that the drag coefficient
changes with the heavy quark mass, while the diffusion constant does not. The
fractional collisional energy loss is much larger than the leading order
estimates from a wQGP because of the core repulsion. Following recent
suggestions, we show how the cQGP results can be translated to the sQGP results
in the $T=(1-3)T_c$ range.
