Casimir Effect for Tachyonic Fields

In this paper we examine the Casimir effect for the case of a tachyonic field corresponding to particles with negative four-momentum squared, i.e., m² < 0. We consider here only the case of the one dimensional, scalar field. In order to describe tachyonic field, we use the absolute synchronization scheme preserving Lorentz invariance. The renormalized vacuum energy is calculated by means of the Abel-Plana formula. Finally, the Casimir energy and Casimir force as the functions of distance are obtained. In order to compare the resulting formula with the standard one, we calculate the Casimir energy and Casimir force for massive, scalar field (m² > 0).