  The dynamics of an electronic system interacting with an electromagnetic
field is investigated within mixed quantum-classical theory. Beyond the
classical path approximation (where we ignore all feedback from the electronic
system on the photon field), we consider all electron-photon interactions
explicitly according to Ehrenfest (i.e. mean-field) dynamics and a set of
coupled Maxwell-Liouville equations. Because Ehrenfest dynamics cannot capture
certain quantum features of the photon field correctly, we propose a new
Ehrenfest+R method that can recover (by construction) spontaneous emission
while also distinguishing between electromagnetic fluctuations and coherent
emission.
