RELATIVISTIC CAUSALITY IN SPONTANEOUS EMISSION BY ATOMS IN A MICROSCOPIC CAVITY

We demonstrate that the principle of relativistic causality is verifie d within the process of two-atom super-radiance by transverse interact ion under the condition of strong microcavity confinement. In particul ar, the effect of vacuum confinement in transverse coupling is found t o be expressed by an infinite series of causal step functions. This re sult, obtained exactly within the framework of non-relativistic quantu m theory is found to be structurally similar to the one of the Green's function theory in relativistic QED. For this purpose, we provide the first evaluation of the free-field commutator, of the chronological-p airing and of the field propagator in microcavity QED.