readily accepted that the wave theory of light had proved itself in explaining
diffraction, interference, reflection and refraction, and that it would
probably never be replaced by another theory. However, this success he pointed
out, rested on the vital fact that all these optical phenomena involved the
behaviour of light over a period of time, and any particle – like properties
would not be manifest. The situation was starkly different when it came to the virtually
‘instantaneous’ emission and absorption of light.