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arXiv · hep-th/9810131

The electromagnetic field near a dielectric half-space

Adam D. Helfer·Andrew S. I. D. Lang
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Abstract

We compute the expectations of the squares of the electric and magnetic fields in the vacuum region outside a half-space filled with a uniform non-dispersive dielectric. This gives predictions for the Casimir-Polder force on an atom in the `retarded' regime near a dielectric. We also find a positive energy density due to the electromagnetic field. This would lead, in the case of two parallel dielectric half-spaces, to a positive, separation-independent contribution to the energy density, besides the negative, separation-dependent Casimir energy. Rough estimates suggest that for a very wide range of cases, perhaps including all realizable ones, the total energy density between the half-spaces is positive.

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Adam D. Helfer, Andrew S. I. D. Lang. 1998-10-16. The electromagnetic field near a dielectric half-space. https://doi.org/10.1088/0305-4470%2F32%2F10%2F011

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