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Anomalous precession

  1. Feb 17, 2012 #1
    There is so much confusion regarding the anomalous precession of Mercury's orbit. Mercury's orbit precesses at 575 arc-secs a century. Classical mechanics accounts for all except the anomalous 43 arc-secs.
    General relativity (curved space-time) accounts for the 43 secs. There are other theories which account for this anomaly in flat, Euclidean geometry. Some doubt that classical perturbation methods can correctly account for the full precession. Some tell us that radiation pressure can account for this anomaly as well. I can go on ...
    Can somebody tell me the orbital precession rate of the earth, Venus, Mars, Jupiter, or Saturn? I need it to check my new model of gravity.
     
  2. jcsd
  3. Feb 17, 2012 #2

    Bill_K

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    SinghRP, I am not aware of any confusion surrounding the anomalous advance of perihelion in Mercury's orbit, although it may be that you have some yourself.

    Do you have access to Wikipedia? Because the answer to your question is easily found there: "The perihelion shift of Earth's orbit due to general relativity is of 3.84 seconds of arc per century, and Venus's is 8.62". Both values are in good agreement with observation."
     
  4. Feb 17, 2012 #3
    Thanks for the orbital precession rates of the earth, Venus, and Jupiter.

    Yes, there is confusion galore! Here are a few references:

    T. Biswas, Special Relativistic Newtonian Gravity,
    Foundations of Physics, Vol. 24, No. 4, 1994.

    H. Behera and P. C. Naik, A flat space-time relativistic
    explanation for the perihelion advance of Mercury,
    http://arxiv:astro-ph/0306611, 2003.

    J. M. C. Montanus, Flat Space Gravitation,
    Foundations of Physics, Vol. 35, No. 9, 2005.

    R. L. Kurucz, The precession of Mercury and the
    deflection of starlight from special relativity alone,
    http://arxiv:astro-ph/0608434, 2006.

    D. Barwacz, Orbital Precession without GR [General
    Relativity], General Science Journal, 2012.

    Note the first ref. It accounts for all the three older predicstions of GR.
     
  5. Feb 17, 2012 #4

    Bill_K

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    SinghRP, I take it back - there definitely is some confusion.
     
  6. Feb 17, 2012 #5

    bcrowell

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    Foundations of Physics was a junk/kook journal before 't Hooft took over as editor in 2007. No, there is no confusion on this issue. There was some confusion in the 70's (described in Clifford Will's Was Einstein Right?), but it has been resolved.
     
  7. Feb 18, 2012 #6
    The last response is not of a scientific nature! Please keep such comments in politics.

    I have read Biswas's and Barwacz's papers very carefully. There is nothing wrong in there. Please read those papers and then come back. I will be here to hear from you.

    Meanwhile, does any one know the complete magnitude of Venus' orbital precession, inclusing the anomalous part? For instance the complete orbital precession of Mercury is 575 arc-secs. a century, of which classical mechanical appriximation methods account for about 531 arc-secs.
     
  8. Feb 18, 2012 #7

    Bill_K

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    I don't have access to those journals or the desire to read them, but I looked at the paper by Behera. He bases his argument on "Maxwellian Gravity", claiming that gravity is a relativstic vector theory, just like electromagnetism, coupled to a conserved vector, a "mass current density." Ok, this is already complete baloney for many reasons. One is that there is no such current, another is that it would imply dipole radiation, wrong deflection of light, and so on.

    It's well known that the perihelion advance predicted by general relativity is twice that of special relativity alone. So how does he manage to get that factor of two to come out? Easy, he calculates the perihelion advance and the Thomas precession and adds them together!
     
  9. Feb 19, 2012 #8

    edguy99

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    You may find this helpful
    planet_precession.gif

    from http://mathpages.com/rr/s6-02/6-02.htm
     
  10. Feb 19, 2012 #9

    bcrowell

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    Edguy99, the table you listed gives the predictions from GR. Observations are listed farther up on the same web page.

    Here http://relativity.livingreviews.org/Articles/lrr-2006-3/index.html [Broken] is a relevant section from a review article on tests of GR.

    This has been a settled issue since ca. 1980. In the 1970's, there were claims that the sun's oblateness was extremely large, much larger than expected from its rate of rotation. This would have messed up the agreement between GR and experiment for Mercury's precession. The oblateness measurements have since been shown to be incorrect.
     
    Last edited by a moderator: May 5, 2017
  11. Feb 19, 2012 #10
    Bill K, thank you for your comments.

    Regarding the papers of Behera-Naik and of Kurucz, even though I did not find anything wrong mathematically, as a physicist I had difficulty grasping them.

    Regarding Biswas’ and Barwacz’ papers, I did not find problems either as a mathematician or as a physicist. I urge you to reconsider your decision and please read these two papers. I am almost sure you would come close to agreeing with me. If not, I will know why.

    I have no problems with general relativity (GR) as a mathematician. But as a physicist, I am looking forward.

    I don’t believe that space-time geometry field, which is the gravitational field in GR, would bring gravity under the fold of the fundamental forces. (It could be that there are one or more fundamental forces in between the weak and gravitational.) Looking at the first three fundamental forces (the strong, the weak, and electromagnetic), I ‘visualize’ that they are mediated by the respective (the color, the weak, and electromagnetic) fields associated with respective properties (the color, the weak, and electrical) charges. I also ‘visualize’ that both static and dynamic states of these charges contribute to the forces.

    Next problem. How come a gravitational interaction which is 10**40 times weaker than an electromagnetic interaction can generate gravitational waves propagating at the speed of light?

    Next problem. General relativity predicts that a light ray is deflected by 1.74 arc-seconds when passing near the sun. The 1919 expedition reported its confirmation; however, later expeditions yielded 2.2 to 3 arc-secs. We are not aware of any observation/experiment which has replicated the 1.74 arc-secs deflection. We doubt that it is humanly, scientifically possible to ascertain the types and intensities of all non-gravitational effects in stellar atmospheres and isolate them – especially when such small quantities are measured. Refractions in the sun’s atmosphere, in the earth’s atmosphere, and in the media in between are not clearly ascertainable either. Some examples of non-gravitational effects in stellar atmospheres: intense electromagnetic fields, high electric fields due to gas ionization, intense currents in stellar gas, high gas pressure, Doppler shifts in high-temperature gas, Wolf effect, etc.

    There are other aspects of GR which have not been tested. Further down, I am lost in the strings, supersymmetry, hidden dimensions, and quantum gravity.

    I am working on a theory that COULD bring gravity in line with the fundamental forces. In that regard, I used Mercury’s orbital precession rate to re-calculate the classical gravitational constant. I need a different orbital precession rate to check my theory. I believe Venus’ would be the right one. I need the full magnitude of the precession, not the GR part only. (Thank you edguy99 for the table. Thank you bcrowell for noting that they were GR parts only.)

    Any one?
     
  12. Feb 19, 2012 #11

    Bill_K

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    I think your questions have been answered.

    Regarding "your theory", please note what it says in the FAQ at the top of this forum: "This forum not meant as a soapbox for those who wish to argue Relativity's validity, or advertise their own personal theories."
     
  13. Feb 19, 2012 #12
    Bill K, Fair enough.
    Regardless, what's Venus' total orbital precession rate?
    After this, I will leave this thread alone.
     
  14. Feb 22, 2012 #13
    I did some searching. Here is what I found.

    Venus' orbital precession rate: 204 arc-sec/century; special relativistic correction: 8.6 arc-sec/century.

    An observer measures Mercury's orbital precession rate to be 5600 arc-sec/century. After filtering out observer-Mercury relative motions, 575 arc-sec/century is left, of which 572 arc-sec/century is due to classical gravity and 43 arc-sec is due to special-relativistic correction.

    Cheers!
     
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