Light Deflection by Exact Plane Waves in Einstein Theory

摘要

The propagation of light rays in purely electromagnetic or gravitational pp-wave solutions of the Einstein equations is studied using simple analytical examples. Thése waves can act as converging or as diverging lenses and a wave can possibly exhibit both behaviours alternatively if light propagates through it for a sufficiently long time. Impulsive waves acting as anastygmatic converging lenses are studied as a limiting case, and it is shown that anastygmatism is a property restricted to purely electromagnetic waves. Previous results are recovered and an independent proof is given. Overall, the physics of light deflection in these waves is surprisingly rich.