Light ALWAYS travels in its idea of a straight-line.
Always.
It doesn’t matter whether it is bent by gravity or refraction, from its perspective, it kept going straight.
Only an “outside viewer” sees any non-straight-line-ness being done, but the outside-viewer isn’t seeing the curved-space or the curved-refractive-index that the photon saw.
Well, kinda, but the trajectory of the photon is contracted into a single point from its POV. Whatever destination is has, it’s already there as far as it’s concerned. It doesn’t experience time given that it’s moving at the speed of light.
maybe somebody else pointed this out:
Light ALWAYS travels in its idea of a straight-line.
Always.
It doesn’t matter whether it is bent by gravity or refraction, from its perspective, it kept going straight.
Only an “outside viewer” sees any non-straight-line-ness being done, but the outside-viewer isn’t seeing the curved-space or the curved-refractive-index that the photon saw.
Well, kinda, but the trajectory of the photon is contracted into a single point from its POV. Whatever destination is has, it’s already there as far as it’s concerned. It doesn’t experience time given that it’s moving at the speed of light.