PRODUCTION OF PHOTONS BY THE PARAMETRIC RESONANCE IN THE DYNAMICAL CASIMIR EFFECT

We calculate the number of photons produced by the parametric resonanc e in a cavity with vibrating walls. We consider the case that the freq uency of vibrating wall is n omega(1) (n=1,2,3,...), which is a genera lization of other works considering only 2 omega(1), where omega(1) is the fundamental-mode frequency of the electromagnetic field in the ca vity. For the calculation of time evolution of quantum fields, we intr oduce a method that is borrowed from the time-dependent perturbation t heory of the usual quantum mechanics. This perturbation method makes i t possible to calculate the photon number for any n and to observe cle arly the effect of the parametric resonance. [S1050-2947(97)09511-5].