INTENSITY-DEPENDENT MASS SHIFT AND SYMMETRY BREAKING

We analyse the effects of the intensity-dependent mass shift predicted for elections in an electromagnetic plane wave on bound states. It is shown that the null result of the experiment of Mowat et al. on the ¹³³Cs ground-state hyperfine splitting was to be expected, although their hypothetical explanation of it is incorrect. The recent suggestion that an intense laser beam might effect the restoration of a spontaneously broken symmetry is examined in more detail, and it is demonstrated that although a pure plane will not suffice, a superposition of plane waves, for example a standing wave, would do so. At present, however, the effect is unobservable small.