Gravitational Lensing and Frequency-Dependent Light Travel Time

[wolram]

Light that has traveled millions of years is gravitationaly (lensed) around a body,
if there is any frequency dependent light travel time ,would it not show up as if it
had been split by a prism when it was lensed around said body, or would the various frequencies recombine?

 

[cesiumfrog]

Basically no, the path-bending of null geodesics in GR is independent of colour (indeed, colour is relative).

There are other arguments to consider, the most significant being the recent possible observation that high energy photons move at slightly different speeds (think "vacuum" refractive-index).

 

[wolram]

Basically no, the path-bending of null geodesics in GR is independent of colour (indeed, colour is relative).

There are other arguments to consider, the most significant being the recent possible observation that high energy photons move at slightly different speeds (think "vacuum" refractive-index).

Thanks cf, i do not know what , "vacuum" refractive-index is, i will look it up, i have an idea but could be way out.

 

[wolram]

The only papers i can find with (vacuum refractive index ) are sub only.