A perfectly conducting surface in electrodynamics with Lorentz symmetry breaking

Abstract

Abstract In this paper we consider a model which exhibits explicit Lorentz symmetry breaking due to the presence of a single background vector $$v^{\mu }$$ vμ coupled to the gauge field. We investigate such a theory in the vicinity of a perfectly conducting plate for different configurations of $$v^{\mu }$$ vμ . First we consider no restrictions on the components of the background vector and we treat it perturbatively up to second order. Next, we treat $$v^{\mu }$$ vμ exactly for two special cases: the first one is when it has only components parallel to the plate, and the second one when it has a single component perpendicular to the plate. For all these configurations, the propagator for the gauge field and the interaction force between the plate and a point-like electric charge are computed. Surprisingly, it is shown that the image method is valid in our model and we argue that it is a non-trivial result. We show there arises a torque on the mirror with respect to its positioning in the background field when it interacts with a point-like charge. It is a new effect with no counterpart in theories with Lorentz symmetry in the presence of a perfect mirror.