Scalar Casimir effect with non-local boundary conditions

Abstract

Non-local boundary conditions have been considered in theoretical high-energy physics with emphasis on one-loop quantum cosmology, one-loop conformal anomalies, Bose-Einstein condensation models and spectral branes. We have therefore studied the Wightman function, the vacuum expectation value of the field square and the energy-momentum tensor for a massive scalar field satisfying non-local boundary conditions on a single and two parallel plates. Interestingly, we find that suitable choices of the kernel in the non-local boundary conditions lead to forces acting on the plates that can be repulsive for intermediate distances.

Brief report prepared for the QG3 session of the MG11 Conference (Berlin, July 2006). In the final version, the third institution of the first author and reference 4 have been added