Steve
Penultimate Amazing
It's the idea from a while ago.
There are three clocks here, a source's clock, an observer's clock, and then I gave the photon a clock.
If the photon's clock falls off, it's still traveling at c against it's own clock, but not an observer's, it will be c/(1+D/H)2 where H=25 Gly.
This solves the reflection problem:
https://mikehelland.github.io/hubbles-law/other/reflection_nm.htm
Hope the photon sent a nice thank you note.
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