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Gravity Probe B and 'frame dragging'

  1. May 8, 2008 #1


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    Am I right in assuming that Gravity Probe B has proved that the rotation of the earth (@~465metres /sec.) 'swirls' space-time in the same sort of way that a rotating ball will swirl a fluid?

    I ask because if this is the case, then the forward motion of the earth (@~360km/sec.) must also produce a linear dragging which is detectable, much like a speedboat leaves a wake in it's path.

    Also, if the rotating mass of the earth causes frame dragging then common sense insists that matter must also 'displace' space time in a manner similar to Archimedes principle.
  2. jcsd
  3. May 8, 2008 #2
    Hi Ian,

    as far as I lnow after over forty years in the making they are still analysing the data of gravity probe B and we are still waiting for the 2 sigma confidence level results. The frame dragging effect is microscopic and was unfortunately swamped by noise in the data that is something like a hundreds times larger than the signal they are looking for, which is why it is taking so long to analyse.

    Not sure about the linear dragging effect.

    A good thread monitoring the progress of Gravity Probe B results is here https://www.physicsforums.com/showthread.php?t=104694&page=20
  4. May 8, 2008 #3
    Maybe not. I think the Michelson Morley type tests would have detected it. More likely the forward motion of the earth is orbiting synchronously with a latent frame dragging caused during the origin of the solar system.
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