The effects induced by the quantum vacuum fluctuations of one massless real
scalar field on a configuration of two partially transparent plates are
investigated. The physical properties of the infinitely thin plates are
simulated by means of Dirac-δ−δ′ point interactions. It is
shown that the distortion caused on the fluctuations by this external
background gives rise to a generalization of Robin boundary conditions. The
T-operator for potentials concentrated on points with non defined parity is
computed with total generality. The quantum vacuum interaction energy between
the two plates is computed using the TGTG formula to find positive, negative,
and zero Casimir energies. The parity properties of the δ−δ′
potential allow repulsive quantum vacuum force between identical plates.Comment: 21 pages and 11 figures. PhysRev