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A theory of gravity based on special relativity

  1. Dec 16, 2005 #1

    Garth

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    A paper by Hai-Long Zhao A theory of gravity based on special relativity
    This is an alternative gravitational theory that has incorporated the conservation of gravitational energy (Zhao's "mass variance") in SR, Self Creation Cosmology has done so in GR (see Resolving the Degeneracy: Experimental tests of the New Self Creation Cosmology and a heterodox prediction for Gravity Probe B).

    Both theories may be falsified - along with GR - in the geodetic and frame-dragging measurements of the Gravity Probe B experiment, which at present is in the data analysis stage.

    We wait and see!

    Garth
     
    Last edited: Dec 16, 2005
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  3. Dec 17, 2005 #2

    Garth

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    Just to make it absolutely clear when the GP-B results are published:
    The predictions of three competing theories, General Relativity (GR), Self Creation Cosmology (SCC) and Zhao's 'Mass Variance SR theory (MVSR) now read:

    1. GPB Geodetic precession
    GR = 6.6144 arcsec/yr
    SCC = 4.4096 arcsec/yr
    MVSR = 0.0000 arcsec/yr


    2. GPB gravitomagnetic frame dragging precession
    GR = 0.0409 arcsec/yr
    SCC = 0.0409 arcsec/yr
    MVSR = 0.0102 arcsec/yr


    So there does seem to have been a point in carrying out that experiment, all three theories may be falsified by the results.

    We wait and see! :smile:

    Garth
     
    Last edited: Dec 17, 2005
  4. Dec 17, 2005 #3

    SpaceTiger

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    Garth, do you know the expected error bars on these measurements?
     
  5. Dec 17, 2005 #4

    Garth

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    SpaceTiger thank you for your question.

    The error bars will be evaluated when the data is processed, the data is in a highly compact and concatenated form at present (see Bob Kahn's paper "Gravity Probe B mission ends" in Matters of Gravity (page 12)). They have carried out calibration trials of many kinds (see their website past highlights for details) in order to evaluate the errors.

    They have published an expected accuracy of the geodetic measurement of 0.01% and the frame-dragging measurement of 1%. These two alternative theories above make gross deviations from the GR predictions and so the results should be clear to many many sigma!

    Garth
     
    Last edited: Dec 17, 2005
  6. Dec 17, 2005 #5

    SpaceTiger

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    Ok, that's all I wanted to know. So...if the results confirm GR, will you consider your theory completely falsified?
     
  7. Dec 17, 2005 #6

    Garth

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    Basically yes, but first I would look into the Thomas precession again. If you have followed my meanderings on the Self Creation Cosmology thread you will have seen that whereas SCC predicts a geodetic precession of 5/6 that of GR, in SCC, but not GR, there is also a Thomas precession to allow for, which works out as 1/6 the GR geodetic precession. If you compare the literature (MTW page 1119 eq 40.34) and Will Covariant Calculation of General Relativistic Effects in an Orbiting Gyroscope Experiment eq 21 you will see the same expression for the geodetic precession but with a reversed sign convention. There are double negatives all over the place!

    When I added the Thomas precession initially I used the wrong convention and added the two precessions making the SCC prediction equal to that of GR. I have since reworked the Thomas precession and am convinced that it should be subtracted, making the SCC prediction 2/3 that of GR.

    If the experiment actually does turn up the 6.6 arcsec/yr value (as everybody expects) I shall look at that one more time before putting SCC to bed for good.

    The definitive test is to see whether particles and photons fall at the same rate or not, SCC predicts photons should fall (accelerate) at a rate 3/2 that of particles. One consequence of this is the LIGO laser half-beams should be attracted towards the Sun daily by 10-12 metres, I have contacted Kip Thorne at LIGO about this and he replied "we do not have very good accuracy on transverse position of the LIGO beam; nowhere nearly good enough to test your predictions."

    If someone did measure the transverse movement and prove that its upper limit is less than the SCC prediction at 3 sigma confidence then that would be an absolute falsification of the theory.

    The really interesting question of course is: "If the results are 4.4"/yr or Zhao's 0"/yr would everybody else consider GR theory to be completely falsified - or would they simply add another epicycle?" :wink:

    Garth
     
    Last edited: Dec 17, 2005
  8. Dec 17, 2005 #7
    Garth
    Just to be clear it’s MVSR that is based on SR
    SCC is based on GR with some modifications, right.

    Is SCC primarily ‘yours’ or is this something several are looking/working at?

    For both SCC and MVSR do you know if the theories have an opinion on the GR prediction of relativistic binary stars accelerating into smaller orbits emitting energy as Gravity Waves; and was ‘measured’ by Hulse & Taylor noble binary pulsar (the accelerating part not the wave)?
    Do they agree or have a different interpretation.

    Myself I’m having trouble buying into any energy needing to leave the binary system at all, but we don’t need to deal with that here.
    RB
     
    Last edited: Dec 17, 2005
  9. Dec 17, 2005 #8

    Garth

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    The theory is primarily 'mine' and the published papers are:-
    On Two Self Creation Cosmologies
    A New Self Creation Cosmology
    and here:
    Self Creation Cosmology - An Alternative Gravitational Theory
    You may not be able to access these, however there is free access of the last two of these papers on the physics ArXiv and the published work can be recovered from there as follows:
    1. The Principles of Self Creation Cosmology and its Comparison with General Relativity
    2. Resolving the Degeneracy: Experimental tests of the New Self Creation Cosmology and a heterodox prediction for Gravity Probe B
    3. The derivation of the coupling constant in the new Self Creation Cosmology
    4. The Self Creation challenge to the cosmological concordance model
    5. Self Creation Cosmology - An Alternative Gravitational Theory however others have also worked on the theory since 1982, there have been to my knowledge 54 other author citations.
    SCC is conformally equivalent to canonical GR in vacuo so it is expected that the gravitational radiation from two point masses orbiting in vacuo would be the same as GR. MVSR also seems to predict the same gravitational radiation as GR.
    Garth
     
    Last edited: Dec 17, 2005
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