DrGreg
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Well, sort of.jimmysnyder said:I'm sorry for completely mischaracterizing the nature of the discussion in this thread. Is the issue that the following two arguments are on equal footing?
1. No one has detected a dependence of the speed of light on the motion of the emiter relative to the observer, therefore the dependence does not exist.
2. No one has detected the luminiferous aether, nonetheless the aether does exist.
There is a difference between the "one-way speed of light" measured from A-to-B, and the "two-way average speed of light" measured on a round trip A-to-B-to-A again. The constancy of the 2-way speed (relative to any inertial observer A) is something that can be confirmed by experiment. The constancy of the 1-way speed depends on your convention for synchronizing the clocks at A and B. If you adopt Einstein's postulates, you must synchronize in such a way that the speed of light is constant by definition.
But you could synchronize in a different way such that all observers agree on what is simultaneous. The second way is just a change of time coordinates tether = teinstein + v0 . x / c2, so still valid. (v0 is the velocity of the observer relative to whatever you arbitrarily choose to be your ether.) But it's an awful choice because you've destroyed all the isotropy of Einstein's co-ordinates. The one thing in favour of "Ether" coordinates is that those people who fail to grasp the concept of relative simultaneity (or those who do grasp it, but philosophically reject it) might be able to accept them.