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MOND GR vs. observations?

  1. Jul 14, 2007 #1

    quasar987

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    I heard a general theory of relativity was constructed based on MOND rather than on Newton's law of gravitation. How well do the predictions of the MOND GR compare with the classical tests of GR (such as light bending)?

    Basically, is it in better or worse agreement with experiment than Newtonian GR?
     
  2. jcsd
  3. Jul 14, 2007 #2

    arivero

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    A related point is... can MOND adjust for the bullet cluster?
     
  4. Jul 14, 2007 #3
  5. Jul 15, 2007 #4

    quasar987

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    Awesome ccdantas :!!)
     
  6. Jul 16, 2007 #5

    Chronos

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    MOND is not dead, but does appear injured. The bullet cluster does pose a difficult [albeit not insurmountable] problem for the model. The links provided by Christina provide a broad picture of current status.
     
  7. Jul 16, 2007 #6

    arivero

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    Are there other experimental counterexamples (falsations) besides the Bullet cluster?
     
  8. Jul 18, 2007 #7
    I am still inclined to believe that there must be something really profound behind the "empric" MOND factor a/(a^2 + a0^2)^1/2, especially taking into acount the "coincidence" that the best fit a0 (1.2*10-10 ms-2) is very close to c(lambda/3)^1/2

    check :

    "MOND as modified inertia" by Milgrom

    http://arxiv.org/abs/astro-ph/0510117v1

    really, really intriguing, don't you think so, another "numerical coincidence" ?
     
  9. Jul 19, 2007 #8

    Chronos

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    It sounds suspiciously numerological to me chrisina, but, that is strictly my personal perspective - more hunch than reason. The standard model with 'dark' tweaks remains more attractive to me. Remember the atom - it's existence was postulated many centuries before is was cornered in a laboratory.
     
  10. Jul 19, 2007 #9
    I also prefer the "dark tweaks", (maybe I was influenced by Dark Vador too much when I was a kid... lol).
    I am just very puzzled at how the curvature radius of a 4D de Sitter universe specified by the cosmological constant (3/lambda)^1/2 seems to play a very important role for the energy distribution profiles of the individual galaxies.
    This requires an explanation.
     
  11. Jul 19, 2007 #10
  12. Aug 26, 2007 #11

    arivero

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  13. Aug 27, 2007 #12
  14. Aug 27, 2007 #13

    jal

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  15. Aug 27, 2007 #14

    CarlB

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    The MOND effect causes an increase in the gravitational strength at long distances. I suppose that an increase in the long distance gravitational strength could cause all matter to be concentrated in small regions. But I'm just guessing. This is way outside my realm of mediocrity.
     
  16. Aug 28, 2007 #15

    Chronos

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    Garth is a very bright guy. He might be luring you into a serious discussion.
     
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