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Michealson & Morley on LIGO

  1. Feb 13, 2016 #1
    Would it be possible to duplicate the Michealson & Morely experiment using LIGO data?

    Essentially the geometry seems to be the same , so I was wondering whether it would be possible verify the M&M result at a much higher resolution using existing LIGO data or is the stability not designed to work at long enough time scales? Maybe the data is pre-filtered to only keep relatively high frequency data.

    Maybe the
  2. jcsd
  3. Feb 13, 2016 #2


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    LIGO is essentially a form of Michelson & Morley experiment. Instead of looking for a continuous ether traveling in a single direction, LIGO is looking for brief (and extremely small) changes in spacetime between the two paths due to the passing of a gravitational wave.

    More information on LIGO's Interferometer.
    Last edited: Feb 13, 2016
  4. Feb 13, 2016 #3
    yes, I realise that , that is why I asked the question.

    The questions is more about the data interferometer than about the interferometer. Since they are focussed on relatively high frequencies , they may have filtered out anything long enough to inform about motion through the ether. I guess that would require very low frequencies 0.16 per hour max. preferable one per day.

    I suspect the machine has not been designed to provide that kind of stability.
  5. Feb 13, 2016 #4

    Vanadium 50

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    There is no need to build a more accurate MM experiment. The few people who are not convinced by the existing data will not be convinced by this.

    Running LIGO for a year continuously, because of events like earthquakes, is impossible. There used to be problems with earth tides as well, I don't know if these were solved or not. They are more predictable.

    So, it's both impossible and unnecessary, which explains why it doesn't happen.
  6. Feb 13, 2016 #5
    It is not a case of convincing anyone who is not convinced. MM proved that there was not a detectable effect within the limits of their apparatus. Anyone who is "convinced" of more than that is not being scientific.

    IIRC, MM was only a couple of meters long on each leg. If LIGO is capable of adding a couple of orders of magnitude to what was done over 100y ago , it would be interesting. But maybe it is not possible within the constraints of an earthbound system.
  7. Feb 13, 2016 #6


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    I'm quite sure Vanadium meant what he wrote - that is the existing data, all of it, and not just the original M&M experiment.
    See here:
  8. Feb 13, 2016 #7
    Thanks Bandersnatch, nice resume.
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