# Absolute Reference Frame

2inquisitive said:
Dale, the diagrams are posted at the site I gave the link to. Here again:
http://www.timing.com/products/pubs/Airborn_ Platforms.pdf
In the rest frame of the geostationary satellite: the photon is reflected straight toward the Earth's surface, which said surface is rotating. During the flight of the photon, the surface/detector move to the right assuming you are looking north from a frame at rest wrt the satellite. The photon hits the ground to the west (behind) the moving detector. This is what happens in actual experiments. Assume the same scenario, except you are at rest wrt the detector: if the photon retained the motion of the moving reflector, it would hit to the east (in front of) of the stationary detector. This frame is incorrect. If the photon did not retain any forward momentum of the moving reflector, the photon would travel directly to the detector. This frame is also incorrect. The photon hits behind (to the west) of the detector in reality. The only frame to give correct results is if a photon leaves a moving or stationary emitter/reflector with no forward momentum, then travels toward the detector, which moves while the photon is in flight. The rest frame of the emitter is the frame which reflects actual results.
Now I really don't understand what you are talking about. Are you talking about figure 1? There are no mirrors/reflectors there (nor in any other figures). Are you describing tower 1 as the emitter, the satellite as the reflector, and tower 2 as the detector? What do you mean by "straight"? Particularly when you are describing geometry in the rotating frame where light does not travel along paths that can be described by x=mt+b. Finally, the satellite is in a geosynchronous orbit so the satellite's rest frame is also a rest frame for the towers, so you cannot possibly have different results in the satellite's and tower's rest frames since they are the same!

Please describe in complete detail the experiment you are proposing, the measurement you are analyzing, and the paradox you think you obtain. By "complete detail" I mean as though you were writing a problem for a textbook. Otherwise there is no paradox, just an incomplete description.

-Dale

2inquisitive said:
The detector has no rest frame unless you can identify an absolute rest frame.
Any object has an infinite number of rest frames. A rest frame is just a frame where the time derivative of the object's position is 0.

In any frame where the time derivitave of the position of a geosynchronous satellite is 0 the time derivative of the position of a tower is also 0. Therefore, not only does the detector have a rest frame, but any rest frame of the satellite is also a rest frame of the detector.

-Dale

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