1993/10/25 by R. D. Daniels, G. M. Shore · 1 citation
Physics and Astronomy · #hep-th #gr-qc
paper · pdf · doi:10.1016/0550-3213(94)90291-7
published as Nucl.Phys.B425:634-650,1994 · 17pages, SWAT 93-9, UGVA-DPT 1993/08-830 (includes three macros undefined in originally submitted version)
arxiv created 1993/10/25 · arxiv updated 2009/11/30
Photons propagating in curved spacetime may, depending on their direction and polarisation, have velocities exceeding the ``speed of light'' c. This phenomenon arises through vacuum polarisation in QED and is a tidal gravitational effect depending on the local curvature. It implies that the Principle of Equivalence does not hold for interacting quantum field theories in curved spacetime and reflects a quantum violation of local Lorentz invariance. These results are illustrated for the propagation of photons in the Reissner-Nordström spacetime characterising a charged black hole. A general analysis of electromagnetic as well as gravitational birefringence is presented.