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I deleted the line about incompatibility witn modern shift experiments
I deleted the line about incompatibility with modern shift experiments,
"4 The results of high speed reenactments of the Ives-Stilwell experiment disagree with the emission theory"
Because, AFAIK, these experiments don't tend to claim to be run and analysed in such a way to make them useful for comparing the shift predictions of emission theory against those of current theory.
Researchers may well fully expect these results to be incompatible with emission theory, but that's not the same thing as actually having demonstrated it.
My understanding of the experimental literature is that while the specific Ives-Stilwell results are in conflict with emission theory, later experimenters have questioned whether the claimed accuracy of that test could have been as good as claimed, given the equipment used. The aspect of I-S that has been repeatedly verified with more accurate equipment since ... that real-world Doppler shifts are "redder" than those that we'd predict by saying that the speed of light is simply fixed in the lab frame ... isn't necessarily in disagreement with emission theory, because emission-theory makes similar prediction. Emission theory has a physical counterpart of SR's "transverse redshift" component, and under emission theory, this component is expected to be stronger than it is under SR.
What the more recent shift experiments usually set out to test was the existence of a redshift deviation from the constant-c predictions of "classical theory" that has "Lorentzlike" characteristics, and that is at least as strong as special relativity. The test theory used doesn't typically doesn't tend to tell experimenters to look for redshifts stronger than those of SR (in the emission-theory range), or to take those stronger redshifts seriously if they do find them, because it's assumed that DeSitter 's results have already ruled out that possibility. According to default test theory, stronger redshifts aren't part of the "analysis window", and we only need to test SR by comparing the predictions of "classical theory" against the redder predictions of SR. Our analysis is typically of the range "CT<-->SR", not "CT<-->SR<-->ET".
When these experiments do find stronger redshifts than SR predicts, they tend to be written off as the side-effects of complicating hardware issues that produce an asymmetrical shift, towards the red (e.g. mirror recoil). In the one test in the literature that actually tried to measure the transverse redshift directly, (Hasselkamp et al, 1979), the experimenters found twice as much redshift as SR predicted, in line with emission theory's predictions ... but reasoned that since this result was obviously wrong, their detector must have been misaligned, and that when one reanalysed the data allowing for a larger angular error in the detector, it was possible to show statistically that SR made a far better match to the data than the idea of a simple fixed speed of light in the lab frame.
So, thanks to the Hasselkamp experiment, we know that analysis for compatibility with the "emission theory" results is not a standard part of the analysis of these more modern experiments, to the extent that it's quite possible to get a result that seems to agree better with emission theory than than SR, and still get it published it in a peer-reviewed journal as supporting SR.
I don't think that we want to discuss any of this in the article.
Points 1-3 seem to provide sufficient arguments against the validity of simple historical emission theory, and seem to be the arguments that the more informed researchers actually use, so I think we should probably stick with those.
Point 4 seems to be valid specifically for Ives-Stilwell, but not so much valid for later experiments, which tended to assume that emission theory was already known to be wrong, and therefore didn't have to be tested for. If we mention Ives-Stilwell in this article as a significant result for emission theory, it opens up the debate as to whether the I-S results were "over-optimistic", which is again getting a bit off-topic.
If we want to mention a more modern experimental result that does legitimately seem to rule out historical emission theory, I think the correct thing to do is to instead quote the 1977 paper by Kenneth Brecher that replicates DeSitter's result for the lack of any obvious distance-dependent signal flight-time offsets in light from double-star systems. ErkDemon (talk) 18:06, 13 June 2008 (UTC)[reply]
Important issues to be found at discussion start - why not in main article?
Concerning de Sitter critique:
'This can be expressed in terms of the "extinction effect", and it arguably undermines the cogency of deSitter type evidence based on optical stars.'
the next reference to tests in the x-ray spectrum still looks to me subject potentially to the photon re-emission/ extinction effect. In the atmosphere for example light is reemitted about every millimetre, and this would not exclude x-rays as far as I am aware. This sort of issue for binary stars was raised by [1] - as referred to in [2].
From the discussion:
'it's quite possible to get a result that seems to agree better with emission theory than than SR, and still get it published it in a peer-reviewed journal as supporting SR.'
'(Hasselkamp et al, 1979), the experimenters found twice as much redshift as SR predicted, in line with emission theory's predictions ... but reasoned that since this result was obviously wrong, their detector must have been misaligned,'
'If we mention Ives-Stilwell in this article as a significant result for emission theory, it opens up the debate as to whether the I-S results were "over-optimistic", which is again getting a bit off-topic.'
The passing points mentioned - regrettably not in the article itself - here are enough to cause outrage about such scientists to someone like me who suspects that these points questions the validity of Special relativity over emission theory/ or other doppler theory light applications. Rarely have I seen such unscientific attitudes as referred. There was also Shankland et al's, misrepensentation of the various interferometry data as indicating insignificant fringe shift levels; just because they were all lower than for a 30km/s relatively moving ether (re. orbiting earth). That 'only' interferometerist Dayton Miller, seemed to take any notice of the still significant fringe shifts often found, shouldn't be the sort of attitude used justify the S - R view when partial ether entrainment can be positted for this.
We are then, amidst a dominant view where the rest of us are generally treated as children who need to read another introductory text book on the subject and so forth. This would miss the much more central issues that surround the details of the referred to experiments themselves, along with addressing the counterarguments concerning supposed validation evidence for special relativity. Recently, work in the microwave range questions the applicability of special relativity: [3]See also [4].
To conclude, was much more interested in those extraordinary revelations from the discussion page, than the pat on the back of dominant physics to be found in the main article - would be brilliant to see these points put into article itself..
[3] 'Absence of the relativistic transverse Doppler shift at microwave frequencies' H W Thim, Instrumentation and Measurement, IEEE Transactions on; Oct 2003, Vol 52, Issue 5, pp 1660-1664
[4] E Baird 'Relativity in Curved Spacetime: Life without Special Relativity.'
Uploaded a new animation of de Sitter's argument against emission theory. I animated the chart recording of the variable star light curve moving to the right, but should it be going to the left? Stigmatella aurantiaca (talk) 11:46, 20 July 2012 (UTC)[reply]
^'Absence of the relativistic transverse Doppler shift at microwave frequencies' H W Thim, Instrumentation and Measurement, IEEE Transactions on; Oct 2003, Vol 52, Issue 5, pp 1660-1664
^E Baird 'Relativity in Curved Spacetime: Life without Special Relativity.'
