Comment on 'Towards gravitationally assisted negative refraction of light by vacuum'
Optics
2009-11-10 v1 Space Physics
Abstract
Reference arXiv:physics/0408021 claims that matter--free regions of spacetime may support electromagnetic waves for which the phase velocity 3-vector is oppositely directed to the power flow 3-vector. This was the definition of negative refraction adopted in \cite{ML}. We here show that this cannot occur in regions of spacetime for which the electromagnetic energy density is positive.
Keywords
Cite
@article{arxiv.physics/0410007,
title = {Comment on 'Towards gravitationally assisted negative refraction of light by vacuum'},
author = {Martin W McCall},
journal= {arXiv preprint arXiv:physics/0410007},
year = {2009}
}
Comments
2 pages A couple of typos corrected