Quantum photon emission from a moving mirror in the nonperturbative regime

We consider the coupling of the electromagnetic vacuum field with an oscillating perfectly-reflecting mirror in the nonrelativistic approximation. As a consequence of the frequency modulation associated to the motion of the mirror, low frequency photons are generated. We calculate the photon emission rate by following a nonperturbative approach, in which the coupling between the field sidebands is taken into account. We show that the usual perturbation theory fails to account correctly for the contribution of TM-polarized vacuum fluctuations that propagate along directions nearly parallel to the plane surface of the mirror. As a result of the modification of the field eigenfunctions, the resonance frequency for photon emission is shifted from its unperturbed value.Comment: 11 pages, 3 figures. To be published in Optics Communication

Reducible systems and embedding procedures in the canonical formalism

We propose a systematic method of dealing with the canonical constrained structure of reducible systems in the Dirac and symplectic approaches which involves an enlargement of phase and configuration spaces, respectively. It is not necessary, as in the Dirac approach, to isolate the independent subset of constraints or to introduce, as in the symplectic analysis, a series of lagrange multipliers-for-lagrange multipiers. This analysis illuminates the close connection between the Dirac and symplectic approaches of treating reducible theories, which is otherwise lacking. The example of p-form gauge fields (p=2,3) is analyzed in details.Comment: Latex 23 pages, some corrections and improvements in the text. To appear in Annals of Physic

A superspace embedding of the Wess-Zumino model

We embed the Wess-Zumino (WZ) model in a wider superspace than the one described by chiral and anti-chiral superfields.Comment: 5 pages, Revtex (multicol