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lalbatros
Aug26-07, 07:37 AM
I quickly read the followoing IEEE paper:

Absence of the Relativistic Transverse Doppler Shift at Microwave Frequencies (http://www.atomicprecision.com/blog/wp-filez/Thim%20-%20Absence%20of%20the%20relativistic%20Doppler%20e ffect%20...%20.pdf)

The author claims he proved that he invalidated experimentally the SR prediction of a transverse Doppler effect for microwaves.
Its experimental setup is shown in figure 1.

Basically, an homodyne frequency-shift detection is used.
It involves a fixed source and a fixed detector.
The setup involves two paths: a "reference path" and an "active path".
In the active path, the microwave beam passes trough a rotating emission-reception system.
Because of the rotation of the beam within the "active path", the author claims a transverse Doppler effect should be observed.
The author did not detect any shift and concluded this invalidates SR.

I think this paper is totally wrong in its analysis and its conclusion. Experimental results are right but useless.
The source and the detector have no relative motion and therefore I would not expect ant Doppler shift.
In addition, if one considers a even simpler version of this experiment, the conclusion of "no Doppler shift expected" is even more obvious to me. This simplified version would be based on a cylindrical cavity in the "active path" whose walls would be rotating. It is clear that rotating walls would make any difference compared with fixed wall: reflexion on perfect conducting walls does not depend on the transverse motion.

I would like to elaborate on my first impression.
I am interrested by your own ideas and comments on this experiement as well as in the basic theory to analyse such experiments in general.

Thanks

Ich
Aug26-07, 03:10 PM
Hi,

I did a quick analysis (http://22214.rapidforum.com/topic=100374605086&startid=2#37460508625640599) of this experiment one year ago, showing that SR predicts a null result, as measured. Sorry it's in German; in English: your first impression is right, emitter and source are at rest, that's it. What's happening between: the wavefront is blueshifted and tilted as seen by the rotating disk, and will be re-emitted blueshifted and tilted. No change happens.

I had a rather lengthy discussion with Prof. Thim via e-mail concerning another paper where he thought to show an inconsistency in the Lorentz Transforms. He emerged as a full scale crank, beyond any reasoning. Hard to believe that he was (is?) still teaching students at the University of Linz.