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Everything else changes but the photon stays the same. The conditions in the local frame at the time of emission are important.
There is red-shift in that case, but it's due to time dilation, not variable speed of light.
In someone else's laboratory, in a very different gravitational field, you will observe their speed of light to be different from c (because their clock is ticking at a different rate).
if you mess around with the speed of light in that manner, you will change v/c and that will break SR.
I don't think that the time dilation of GR totally breaks SR, provided you are conscious of the very limited domain of SR, which was really derived for areas outside a gravitational well. ie nowhere in our current universe (but it's still a very useful approximation...).
Quote from: evan_au on 03/01/2017 10:40:31I don't think that the time dilation of GR totally breaks SR, provided you are conscious of the very limited domain of SR, which was really derived for areas outside a gravitational well. ie nowhere in our current universe (but it's still a very useful approximation...).Consider two local reference frames in a SC potential. Each perceives the other's clock to run slower. You can interpret that as different light speeds, but the clock rate interpretation is more consistent with SR concepts.
Quote from: Mike Gale on 04/01/2017 04:02:18Quote from: evan_au on 03/01/2017 10:40:31I don't think that the time dilation of GR totally breaks SR, provided you are conscious of the very limited domain of SR, which was really derived for areas outside a gravitational well. ie nowhere in our current universe (but it's still a very useful approximation...).Consider two local reference frames in a SC potential. Each perceives the other's clock to run slower. You can interpret that as different light speeds, but the clock rate interpretation is more consistent with SR concepts.The infinitely removed observer perceives different light speeds at different locations, but all free-fall observers (including the infinitely removed one) measure that same light speed at their respective locations.
I think I'm starting to get clued in. His point is that, although the Ricci scalar vanishes, the Ricci tensor does not. Viascience explains the Ricci tensor as a test of conservation of volume. He cites an example where a ring of dust of negligible mass density collapses around a gravitating mass. The inner surface falls faster than the outer one, but if the Ricci tensor is null, the volume will remain constant all the way up to the event horizon. All bets are off at that point because the model fails. My point is that it should start to fail much sooner than that because, in its local reference frame, the inner surface is approaching light speed.
I think somewhere you have doubled up on relativistic terms although I must admit I haven't given this rigorous scrutiny. The fact that you are thinking these ideas through in the first place is praiseworthy in and of itself. Keep it up.