Remarks on Professor Lewis's note on the path of light quanta in an interference field

In an earlier number of these Proceedings, (1) Professor G. N. Lewis adopted an extreme form of the light quantum theory, in which the light quanta are assumed to travel in straight lines except when deflected by matter, the facts of interference being explained by the assumption that the quanta do not go to those places where the wave theory forbids the action of radiation. As a crucial test between this and other theories of light, Professor Lewis proposed an experiment in which the absence of light quanta, traveling over a particular path which leads to the center of of an interference band on a screen, would produce an unbalanced torque on a reflecting mirror.