• Sep 10 2013

    WITS Node Seminar: Prof Herbert Weigel (SU)

    The National Institute for Theoretical Physics, and the Centre for Theoretical Physics, School of Physics, would like to invite to its coming talk in the theoretical physics seminar series, entitled:

    "Attractive Electromagnetic Casimir Stress on a Spherical Dielectric Shell"

    to be presented by Prof. Herbert Weigel (University of Stellenbosch)

    Abstract: Based on calculations involving an idealized boundary condition, it has long been assumed that the Casimir stress on a spherical conducting shell is repulsive. In this talk I review the use of spectral methods to investigate the Casimir (or vacuum polarization) energies. In particular I discuss problems with idealized boundary conditions. They must be avoided by accounting for material properties. For the problem at hand this is accomplished within the more realistic Drude dielectric model. It then turns out that the stress of the shell is actually attractive, matching the generic behavior of Casimir forces in electromagnetism. The discrepancy between these two cases can be linked to interactions between the electromagnetic quantum fluctuations and the dielectric material.

    Date: Tuesday, 10th September 2013
    Venue: Frank Nabarro Lecture Theatre P216
    Time: 13.20 - 14.10