Although the Euler-Heisenberg theory of the scattering of light by light in a vacuum must be considered correct when only a few optical photons are involved, it is by no means certain that this theory remains valid under experimental conditions when the number of photons becomes very large. In this paper the possibility of the existence of collective photon effects is considered, with particular reference to their ability to produce an intensity-dependent refractive index in an optical centre-of-mass interaction region. Experimental preparations being made to search for such an effect are described.

J. Hughes

Papers

A pulse storage system for studying the properties of laser photons