@dalehileman,
Quote: (2) there must be a "stationary ref"
The CMB (CMBr, if you prefer) has been found to be homogenous throughout the universe with accuracy of 1 part in 100,ooo (or something like that).
Yet if we look at the CMB from one direction, it is moving away from us. But if we look at it from the opposite direction, it is approaching us. How can that be?
Note that if you took the position that all inertial frames are equivalent, you could express the exact same thing in a different way:
You could also say that "if we look at the CMB from one direction, WE are moving it away from it. But if we look at it from the opposite direction, WE are approaching the CMB."
It is this second way of expressing it that most astrophysicists agree is correct, and of course that would explain the phenomenon rather simply and easily.
But SR would prohibit us from saying it in the second way. We can never say, in SR, that "we" are moving. It must be the other object.
And, of course, it is an essential postulate of SR that no optical information could possibly, ever, give us any clue as to whether the earth is moving. Without that, they can't even begin to claim that all inertial frames are "equivalent."
But that's rather ironic, isn't it? We can't we say it the second way, if indeed all inertial frames are equivalent?
It seems that, in SR, some pigs are more equal than others (as Orwell might say).
Beyond that, if you say that we are moving wrt to the CMB (rather than vice versa) then we have essentially established a preferred frame (the CMB), which is also prohibited by SR.
But note that this prohibition is NOT founded upon experimental proof. It is, rather, founded upon a deeply held philosophical (metaphysical) belief that SR adherents attempt to impose on all others by fiat.
