Casimir effect from a scattering approach

G.-L. Ingold and A. Lambrecht

Am. J. Phys. 83, 156-162 (2015) DOI: 10.1119/1.4896197

The Casimir force is a spectacular consequence of the existence of vacuum fluctuations and thus deserves a place in courses on quantum theory. We argue that the scattering approach within a one-dimensional field theory is well suited to discuss the Casimir effect. It avoids in a transparent way divergences appearing in the evaluation of the vacuum energy. Furthermore, the scattering approach connects in a natural manner to the standard discussion of one-dimensional scattering problems in a quantum theory course. Finally, it allows to introduce students to the methods employed in the current research literature to determine the Casimir force in real-world systems.