2002/04/30 by V. Sopova, L. H. Ford · 1 citation
Engineering · Physics and Astronomy · #Cosmology and Gravitation Theories #Quantum Electrodynamics and Casimir Effect #Thermal Radiation and Cooling Technologies #gr-qc #hep-th #quant-ph
paper · pdf · doi:10.1103/physrevd.66.045026
published as Phys.Rev. D66 (2002) 045026 · 16 pages, 4 figures; 3 references and some new material in Sect. 4.4 added
arxiv created 2002/06/14 · openalex publication_date 2002/08/26 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
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 dispersive dielectric. We find a positive energy density of the electromagnetic field which diverges at the interface despite the inclusion of dispersion in the calculation. We also investigate the mean squared fields and the energy density in the vacuum region between two parallel half-spaces. Of particular interest is the sign of the energy density. We find that the energy density is described by two terms: a negative position independent (Casimir) term, and a positive position dependent term with a minimum value at the center of the vacuum region. We argue that in some cases, including physically realizable ones, the negative term can dominate in a given region between the two half-spaces, so the overall energy density can be negative in this region.