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Thread: Michelson-Morley experiment in space?

  1. #1
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    Michelson-Morley experiment in space?

    Hello,

    As some on this forum may know, I deal with a lot of crank astronomy claims such as the Electric Universe, Geocentrists, etc. One of the things I'm trying to find, to deal with a geocentrist claim, is to determine if an MMX experiment has ever been flown OFF Earth.

    SOHO/MDI & SDO/HMI are both Michelson Doppler interferometers but their configuration, with the remote light source (in this case the Sun), only provides a test of ballistic light theories. Other Michelson Doppler interferometers flown on satellites seem to have similar configurations with the light coming from the object of study, in many cases Earth itself.

    Does anyone know of an MMX-type experiment that has been flown with the sensitivity, as well as a velocity relative to Earth, sufficient to generate a statistically-significant result?

    It also occurs to me that other types of experiments, such as electromagnetic resonance cavities (atomic clocks in GPS satellites, microwave ovens on the ISS, etc.), might also provide a sufficiently similar test. I actually tried computing some of these possibilities, but I had too many uncertainties in the actual operating configuration to be sure of my calculation. Anyone know if that has been examined?

    If that doesn't exist, I'm wondering, with growth of private launch facilities, citizen science initiatives, etc. would flying such an instrument be a good project for a school or other educational organization? The space shuttle used to have the 'getaway special'. Is there anything similar today?

    The other question is could a sufficiently sensitive MMX be built in the space and weight available for such an effort. So many experiments which were state-of-the-art 100 years ago can be done with off-the-shelf parts today. The original MMX was pretty big, but with improved tech, could it fit in a significantly smaller package? The one I played with in Optics lab was about 12" on a side.

    I know the Geocentrists will claim a null result is a cover-up/conspiracy/etc., but it would nice to have the result, especially if it were done by a group outside the NASA/ESA/etc. ring of 'conspirators'. ;^)

    Thoughts?
    Tom

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    This is a tough one. It's (relatively) easy to convince people in charge of precious space resources to allow a group of elementary school kids to carry out a simple experiment for a week; say, growing beans inside a closed container. It makes for good PR, everyone gets to see smiling kids, the general public will say, "Gee, that's a good question: will the beans taste better?"

    It's much harder to convince administrators to run a more complicated experiment, one which the general public won't understand, and which the scientific community feels is a complete waste of time. Where's the benefit for the space program? If the answer is "It will satisfy the loonies who think that we never went to the Moon ....", then it's going to be rejected every time.

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    I am not talking about an elementary school project. These types of things are being done by advanced groups in high schools, and college undergraduate & graduate programs.

    As Pamela Gay suggested in a recent podcast on ArduSats, students could launch clocks to do their own tests of relativity (oh, I guess I just answered PART of my question involving modern versions of the 'getaway special'). A large part of a scientist's training is learning about what's already been done and repeating some of the experiments. If they can get some of that training launching an actual satellite experiment, that's great.

    Tom

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    Quote Originally Posted by StupendousMan View Post
    and which the scientific community feels is a complete waste of time. Where's the benefit for the space program?
    Canadian Geocentrist Walter Van der Kamp devised a lightweight first-order experiment to test Relativity and the isotropy of space, and initially had the backing of the Royal Society of Canada to have it performed on a Shuttle in 1984, until at the last minute American administrators denied the experiment be taken on board, ruling that the result was "a foregone conclusion" and as you said, "a complete waste of time".
    Last edited by wd40; 2014-Oct-19 at 11:17 PM.

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    I had an idea, but realized there is something I don't understand about it. In general, do geoc entrusts believe that that the earth is rotating in the center of the universe or that the universe rotates around the earth? The reason I ask is if the former, then the pattern should change when the interferometer is rotated (at the equator, for instance) while in the latter case I don't know how you would explain a Foucault pendulum or the shape of the earth...
    As above, so below

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    Robert Zubrin told me that if my group developed a package to
    go into space, he could practically guarantee that we would be
    able to get it launched. That was back when the Space Shuttle
    still had several years of life left. I didn't ask him whether he
    had the Shuttle specifically in mind, or for details of who would
    provide such a launch.

    Unfortunately we never came up with a plan we could carry out,
    so it went nowhere. A MMX would have been a great idea, if it
    could be fitted into a small enough package. I wish someone
    at the time had thought of it.

    -- Jeff, in Minneapolis

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    Jens,

    I imagine that a person can be a geocentrist and still embrace
    Mach's principle.

    -- Jeff, in Minneapolis

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    The proper answer to that geocentrist claim would be: "If you think that a space-based MMX experiment will show that your already invalid idea (check out the phases of Venus!) is still invalid then you should fund the experiment" .
    Or wait until about 2034 and the Laser Interferometer Space Antenna.
    I am not sure what the null results of the Michelson-Morley experiment means in terms of this geocentrist claim.

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    One of the many (and often contradictory) claims is that the MMX null result is evidence that Earth is motionless.

    Geocentrists sometimes invoke Mach's principle because of the popular image by scientists that you can regard the universe revolving around the Earth. But the geocentrists neglect that Mach's principle means you can also build a consistent model with the universe revolving around any other point (Mars, Venus, Pluto, 51 Pegasi) as well.

    Basically they invoke relativity to deny relativity.

    Never said it made logical sense, but actually having an off-Earth MMX to reference is one less point they can claim.

    Tom

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    Quote Originally Posted by wd40 View Post
    Canadian Geocentrist Walter Van der Kamp devised a lightweight first-order experiment to test Relativity and the isotropy of space, and initially had the backing of the Royal Society of Canada to have it performed on a Shuttle in 1984, until at the last minute American administrators denied the experiment be taken on board, ruling that the result was "a foregone conclusion" and as you said, "a complete waste of time".
    That's interesting and should add that to my list.

    Got a reference and a description of the experiment?

    Tom

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    Quote Originally Posted by CrankAstronomy View Post
    Basically they invoke relativity to deny relativity.
    Phil Plait writes here that a relativistic geocentrism (with a small g) that is in accordance with Relativity is acceptable.

    But that an absolutist Geocentrism (with a capital G) is not.

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    Quote Originally Posted by wd40 View Post
    Phil Plait writes here that a relativistic geocentrism (with a small g) that is in accordance with Relativity is acceptable.
    But that an absolutist Geocentrism (with a capital G) is not.
    Do you have a reference for your earlier post? I'd never heard that.
    As above, so below

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    I know you're asking specifically about MMX-type experiments (in space), but I thought I'd add this just in case.

    Depending on what question(s) you're asking an experiment to decide (or at least provide evidence for/against), and on how specific the questions are (yes, it's to do with relativity, and special relativity in particular, but what, exactly?), then a great many 'in space experiments' have been done, whose results can be analyzed to provide at least indirect answers.

    Some examples:
    • GRAIL and GRACE (etc)
    • TDRS(S)
    • transponders on Cassini (etc)
    • VLBI where one radio telescope is in orbit
    • locating GRBs


    Of the planned missions, perhaps the LISA Pathfinder comes closest to an 'MMX in space', due for launch next year (though it wouldn't surprise me in the least to learn that at least some geocentrists dismiss this as being not an MMX at all).

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    Quote Originally Posted by CrankAstronomy View Post
    Got a reference and a description of the experiment?
    According to Van der Kamp's book his first-order experiment to test Special Relativity is in the American Journal of Physics Jan 1985 vol 53 p43-45
    Last edited by wd40; 2014-Oct-20 at 08:15 PM.

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    Here it is:
    Simple first-order test of special relativity

    Thanks. I've added it to my 'retrieve list'

    I probably should have more clearly specified that I mean Geocentrism as opposed to geocentrism.

    I can imagine a number of instruments that might rely on the constancy and isotropy of c that might operate differently if not in a 'preferred' frame. The question is would the sensitivity be sufficient to show up in the instrument operation. Resonance cavities used for monitoring instrument calibrations might be good candidates.

    Thanks,
    Tom

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    Quote Originally Posted by CrankAstronomy View Post
    The paper itself is behind a pay wall but is described in Non-time-orthogonality and Tests of Special Relativity
    An intriguing, and possibly significant, anomalous signal in the Brillet and Hall experiment is contrasted with a simple first order test of special relativity subsequently performed to discount that signal as spurious. Analysis of the non-time-orthogonal nature of the rotating earth frame leads to the conclusion that the latter test needed second order accuracy in order to detect the effect sought, and hence was not sufficient to discount the potential cause of the anomalous signal. The analysis also explains the results found in Sagnac type experiments wherein different media were placed in the path of the light beams
    It is basically a MMX experiment where one arm is sent through water. It was done and the results were "Repeated testing showed no detectable motion of the fringes". This pre-print (no sign of publication) analyses the experiment and says "there will be no observable change in fringe location in the experiment of section 2".

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    Quote Originally Posted by Reality Check View Post
    The paper itself is behind a pay wall but is described in Non-time-orthogonality and Tests of Special Relativity

    It is basically a MMX experiment where one arm is sent through water. It was done and the results were "Repeated testing showed no detectable motion of the fringes". This pre-print (no sign of publication) analyses the experiment and says "there will be no observable change in fringe location in the experiment of section 2".
    I see there are other papers listed as citations to the original article. The abstracts suggest similar null results.

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    Are not the frame dragging results by Earth enough?

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    Frame dragging is a GR effect, the rotational component of which was detected by Gravity Probe B. I do not know if Geocentrism includes that the Earth does not rotate. Maybe Van der Kamp's result is taken by them as evidence that the Earth does not rotate.
    There should also be a linear component from the movement of the Earth but as far as I know it is too difficult to detect it.

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    I was thinking more of an indirect demo that the speed of light is constant...

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    My interest in an off-Earth MMX is that it takes advantage of Geocentrists' claim that an Earth-based MMX is proof Earth does not move. It would be more of an embarrassment for them.

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    What if you put the interferometer on an airplane and then changed the orientation 180 degrees? They can't deny that the plane is moving if the earth isn't.
    As above, so below

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    If the 1000mph of the Earth's rotation is enough to show up fringes for the MGX, would a 1000mph Concorde flying in a straight line be sufficient speed for an MMX-type test?
    Last edited by wd40; 2014-Oct-22 at 02:35 AM.

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    Quote Originally Posted by Jens View Post
    What if you put the interferometer on an airplane and then changed the orientation 180 degrees? They can't deny that the plane is moving if the earth isn't.
    Jens I like the way you think!

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    Jens,

    It isn't clear to me what orientation you are referring to.
    Change the orientation of the interferometer 180 degrees
    relative to the direction of Earth's rotation? Its motion
    around the Sun? Around the Galaxy? In the MMX, the
    interferometer always rotates so that observations are
    made in many orientations in the horizontal plane.
    Change the direction that the aircraft (another kind of
    plane) is going by 180 degrees? That shouldn't be
    necessary for the demonstration to work. Any one
    direction should suffice. (Though *of course* anybody
    doing this would fly in as many different directions as
    possible before the money ran out.)

    I agree that what you're suggesting would work, at least
    in principle -- I'm just not sure what you're suggesting.

    A Sagnac interferometer is not the same as the MMX, but
    they are very closely related. The only time I saw one was
    in the lab at Honeywell when they were developing a laser
    ring gyroscope for use on the Boeing 747. It was about ten
    or twelve inches in diameter, and the entire ring was visible,
    glowing red. Could have just been a neon tube...

    Such laser gyros in planes show that the plane is rotating
    while it sits at the terminal, because the Earth is rotating!

    -- Jeff, in Minneapolis
    Last edited by Jeff Root; 2014-Oct-22 at 06:45 AM.

  26. #26
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    I meant to spin it horizontally in the airplane, so that it was facing the nose but now it's facing the tail. And sure, you could also rotate it to face the port or starboard wing. Or of course, you could turn the plane around if the apparatus is too bulky to move in the plane.
    As above, so below

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    Quote Originally Posted by Jeff Root View Post
    Jens,

    Such laser gyros in planes show that the plane is rotating
    while it sits at the terminal, because the Earth is rotating!
    The Geocentrists say that the laser gyro only shows that there is an indistinguishable relative daily movement between the Earth and the universe, whilst the null/zero-velocity MMX result shows to them that the Earth is not going round the Sun, which is why the OP would like to see the MMX carried out away from the Earth in order to silence their claim once and for all. If enough ruckus is raised on Friday, there may indeed be demands by the scientific community to demonstrably silence the Geocentric claim forever and the OP could yet get his wish!
    Last edited by wd40; 2014-Oct-22 at 07:19 PM.

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    Quote Originally Posted by wd40 View Post
    ...there may indeed be demands by the scientific community to demonstrably silence the Geocentric claim forever and the OP could yet get his wish!
    Except that will never happen. Because yet another reason will be found why 'the results are not telling us what you say, they back up my idea really' (cue convoluted, contrived and confounded series of 'explanations'). So why waste the money?

  29. #29
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    Yes: The Geocentrists "logic" seems to go like "We cannot conceive of light waves not propagating in a medium thus the aether exists. If the Earth was moving then the MM experiment would have detected the movement through the aether. The MM experiment did not detect the movement thus the Earth does not move".
    The physical debunking of this is to do the MM experiment in an environment that is moving relative to the Earth and get null results again. Thus in space, on another planet, or in an airplane.

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    Does current technology allow the MMX to be done reliably
    on airplanes? If so, has it been done?

    -- Jeff, in Minneapolis

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