Radiation and Atoms

Abstract

IN the attempts to interpret theoretically the interaction between radiation and matter, two apparently contradictory aspects of the mechanism have been disclosed. On one hand, interference and dispersion demand a continuity similar to that of the classical theory of optics. On the other, the exchange of energy and momentum between radiation and matter presents discontinuous features which have even led to the introduction of the theory of light quanta, denying in its most extreme form the wave constitution of light. The two aspects must be really consistent, but the discontinuous side is apparently the more fundamental, and for this reason any attempt at a consistent interpretation in the present state of science must inevitably appear rather formal. Nevertheless, on the basis of Bohr's correspondence principle, it seems possible to build up a more adequate picture of optical phenomena than has previously existed, by associating the essentially continuous radiation field with the continuity of existence in stationary states, and the discontinuous changes of energy and momentum with the discontinuous transitions from one state to another.