Resonance Radiation and the Correspondence Principle

Abstract

THE experiments of Wood and Ellett¹ on the polarisation of the resonant radiation of mercury suggest that it is necessary to make a rather important modification in the quantum theory. The theory of the phenomenon has been examined by several writers,² among whom Eldridge has most explicitly directed attention to a case of difficulty. He shows that the observations in a magnetic field are a natural consequence of regarding magnetism as equivalent to rotation, provided that the effect without field is given, but that this effect without field conforms rather to the classical than to the quantum theory.