Correspondence rules in macroscopic quantum electrodynamics
Lev I. Plimak · Physical Review A · 1994
It is shown that provided two devices are distinguishable, their electromagnetic interactions are in essence classical. This results in the existence of simple correspondence rules connecting q- and c-number statistical descriptions of macroscopic optical arrangements. These rules allow formulas found by c-number techniques to be used as precise quantum relations. For the vast majority of real devices, including all linear devices and real light detectors regardless of their internal system, their c-number macroscopic description can be directly employed in QED. The problem of locality of QED is discussed and a rigorous theory of electrical-feedback arrangements in optics is presented.