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Why the michelson-morley experiment is not reliable

  1. Aug 21, 2005 #1
    Why the Michelson-Morley experiment is not reliable, and why Einsteins (I dont want to reveal my identity over the internet, but i will include a number which is connected to my identity in a highly complicated way, and i have also taken other precautions, so that i can prove that i was the one that wrote this document and that i was the one that figured it all out.
    Here is my number: 5097330 Sweden )


    Firts of all i am going to explain why the Michelson-Morley experiment is not reliable. If you imagine that you are going to measure the time it takes for a ray of light to go a certain distance. You send a beam to a receiver located 500 metres from the lightsource. And you measure the time it takes for the beam to reach the receiver. If the beam is sent to the reciever in the same direction as the earth goes around the sun, then the receiver will move a little bit in the same direction as the beam goes during the time it takes for the beam to reach the receiver. Therefore the distance that the beam goes will be a little bit longer than the distance between the lightsource and the receiver. And therefore the time it takes for the beam to reach the receiver should be a little bit longer when the beam is sent in the same direction as the earth goes around the sun than when the beam is sent in a direction that is straight across the direction that the Earth goes around the sun. This was what the Michelson-Morley experiment tried to prove. But the experiment did not show any difference in the time it took for the beam to go in the different directions. But the Michelson-Morley experiment is not reliable. If you had performed the experiment the way that i described then you would most certainly discover that the time it takes for the beam to go to the receiver can be affected by the movement of the Earth. The fault with the Michelson-Morley experiment was this: If you imagine that the beam does not go directly to the receiver, instead the beam first goes to a mirror and then reflects back to a receiver which is located almost exactly by the lightsource. When the beam goes from the lightsource to the mirror the beam goes in the same direction as the Earth goes around the sun. Therefore the distance that the beam has to go to the mirror will be a little bit longer than the distance between the light source and the mirror. But when the beam is reflected by the mirror and goes back to the receiver, then the beam goes in the opposite direction as the Earth goes around the sun. Therefore the distance that the beam has to go from the mirror to the receiver will be a little bit shorter than the distance between the mirror and the receiver. And because the distance between the light source and the mirror is almost exactly the same as the distance between the mirror and the receiver, the increase of the distance will be the same as the decrease of the distance. So it even out. Therefore, in the Michelson-Morley experiment, it was impossible for the movement of the Earth to affect the time it took for the beam to reach the receiver. And therefore the Michelson-Morley experiment is not reliable. I am aware of that the Michelson-Morley experiment was not performed in the exact way that i described it. But i have checked up on the real experiment also and i got the same result there. It even out. Other experiments have been performed and have had the same result as the Michelson-Morley experiment. But there is probably some faults in those too. Imagine that you would perform an experiment the way that i desribed it, where the beam goes directly from the lightsource to the receiver without any mirrors. The beam goes in the same direction as the Earth goes around the sun. If the distance betweeen the lightsource and the receiver would be 10 metres instead of 500 metres, then it would probably not be able to detect any effect by the movement of the Earth on the time it takes for the beam to go from the light source to the receiver. The reason why is because the time it takes for the beam to go 10 metres is so short, and during that short time the receiver only moves about a millimetre. And the extra time it takes for the beam to go this extra millimetre is of course even shorter than the time it takes for the beam to go 10 metres. And this short extra time it takes for the beam is not detectable with an atomic clock, assuming that i have understood correctly how an atomic clock works. So my instructions for a reliable experiment is to have as long distance as possible between the lightsource and the receiver, and that the beam shall go directly from the lightsource to the receiver without using any mirrors. And then measure the time it takes for the beam to go from the lightsource to the receiver, both when the beam goes in the same direction as the Earth goes around the sun, and when the beam goes in the opposite direction. Then you would most certainly discover that it will take longer for the beam to reach the receiver if the beam goes in the same direction as the Earth goes around the sun than if the beam goes in the opposite direction. But this does not mean that the speed of light is not constant. The time it takes for the light to go a certain distance is always the same in vacuum, but the time it takes for the light to reach an observer that are moving, is dependent on how fast the observer goes and which way the observer goes. The faster the observer goes in the same direction as the light, the longer it takes for the light to reach the observer. The faster the observer goes in the opposite direction as the light, the shorter it takes for the light to reach the observer.
     
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  3. Aug 21, 2005 #2

    Tide

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    And that is precisely why Michaelson used an interferometer! :)

    You didn't make clear the relationship between the sources, detectors and the observer but I don't see that you have made any comparison with Michaelson-Morley. They were interested in comparing the speed of light both parallel and perpendicular to the "ether" and they were very careful to account for time differences related to both relative positions and orientation.
     
  4. Aug 21, 2005 #3

    LeonhardEuler

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    This is not true, the changes in distance don't even out. (More exactly, they don't even out in the frame of the beam of light using classical transformations. Of course there is no difference in the distance in the instrument's frame since the length doesn't change) On the first trip the target is moving towards the beam. If v is the speed of the target and [itex]t_0[/itex] is the time taken for this trip, then the change in distance is [itex]-vt_0[/itex]. Simmilarly, when the target is moving away, the change is [itex]vt_1[/itex], where [itex]t_1[/itex] is the length of time for this trip. So why do these not cancel? Well, the target is moving away in the first trip, so it takes a longer time to complete this trip than the first trip. Therefore [itex]t_1>t_0[/itex]. The diference in distance is [itex]v(t_1-t_0)[/itex], and therefore it is positive.

    How positive? Using distance equals rate times the time in the first trip gives: (keeping in mind that the distance is shrunk)
    [tex](d - vt_0) = ct_0[/tex]
    [tex]d = t_0(c+v)[/tex]
    [tex]t_0 = \frac{d}{c+v}[/tex]
    For the second trip:
    [tex](d + vt_1) = ct_1[/tex]
    [tex]d = t_1(c-v)[/tex]
    [tex]t_1 = \frac{d}{c-v}[/tex]
    The change in distance is therefore:
    [tex]\frac{d}{c-v} - \frac{d}{c+v} = \frac{2dv}{(c+v)(c-v)}[/tex]

    A final note. The Michelson Morley experiment did not depend on accurate measurements of time. It exploited the fact that the wavelength of visible light is quite small, so a small change in distance can be the difference between constructive and destructive interferance. The beam used to interfere with this one was one sent perpendicular to it. For more details look at http://galileoandeinstein.physics.virginia.edu/lectures/michelson.html
     
  5. Aug 21, 2005 #4

    Doc Al

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