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Amazing new experiment proposed

  1. Mar 26, 2004 #1
    http://science.nasa.gov/headlines/y2004/26mar_einstein.htm?list531723 [Broken]

    This would test the predictions of GR 30,000 times better than the current best test--enough to start verifying predictions made by some of the current proposals for TOEs, in terms of descrepancies.

    Note to mods: I wasn't sure where to put this, so feel free to move it wherever it may be more appropriate.
    Last edited by a moderator: May 1, 2017
  2. jcsd
  3. Mar 26, 2004 #2


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    Actually a scientific use for the ISS! Will wonders never cease.
  4. Mar 26, 2004 #3
    Why is this:

    "The Global Positioning System (GPS), for instance, wouldn't be possible without the theory of relativity."
  5. Mar 27, 2004 #4
    What the article is saying is that unless the time corrections predicted as being necessary by SR are preset into the orbiting clocks, the errors would be so great as to make GPS useless
  6. Mar 27, 2004 #5
    Ahh.. Thats freaking interesting. I wouldn't think there would be enough time difference to even notice. Obviously, I'm wrong. How big of a difference would it be?
  7. Mar 27, 2004 #6
    http://www.metaresearch.org/cosmology/gps-relativity.asp [Broken]
    Last edited by a moderator: May 1, 2017
  8. Mar 27, 2004 #7
    Aycamo----Chen cited one of the Tom Van Flanderan articles - The Loretz-Ether types arrive at the same result as to the need to provide an offset to correct for time dilation.

    Whether you are a stanch relativity advocate or prefer to treat the problem as due to motion with respect to an ether - the equations are the same. The ether types claim there is difference however when it comes to compensating for the earths rotation, i.e., that GPS disproves SR a la the one way Sagnac effect - the relativity boys claim its really a problem for the General theory - but in actuality - it is a classical correction that needs to be made because the receiver is moving with respect to the earth centered reference frame - so during the time required for the satellite signal to arrive, the transmission path length has changed - this corresponds to a fraction of a usec - but light travels about 30 meters in 0.1 usec. So by way of illustration, the clocks do not have to be very far off to generate a large positional error.
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