"

I am not so sure that it eliminates things like population inversions, because one can I think describe them by suitably extended macroscopic variables. I stand to be corrected about this. One finds discussions of negative temperatures which I think refer to population inversions, and one recalls Lamb's paper ""Classical laser"", Borenstein, M., Lamb, W.E. (1972), Physical Review A 5(3):1298-1311.  "