The cutoff-dependence of the Casimir force within an inhomogeneous medium

Abstract

We consider the ground state energy of the electromagnetic field in a piston geometry. In the idealised case, where the piston and the walls of the chamber are taken as perfect mirrors, the Casimir pressure on the piston is finite and independent of the small scale physics of the media that compose the mirrors; the Casimir-energy of the system can be regularised and is cutoff-independent. Yet we find that, when the body of the piston is filled with an inhomogeneous dielectric medium, the Casimir energy is cutoff-dependent, and the value of the pressure is thus inextricably dependent on the detailed behaviour of the mirror and the medium at large wave-vectors. This result is inconsistent with recent proposals for regularising Casimir forces in inhomogeneous media.

6 pages, 2 figures

References in corpus (1)

• Numerical Regularization of Electromagnetic Quantum Fluctuations in Inhomogeneous Dielectric Media

Cited by in corpus (4)

• Electromagnetic description of three-dimensional time-reversal invariant ponderable topological insulators
• First-order correction to the Casimir force within an inhomogeneous medium
• The paradox of the Casimir force in inhomogeneous transformation media
• Regularization just by quantization -- a new approach to the old problem of infinities in quantum field theory (Draft of lecture notes)