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Non-symmetric gravitational theory (NGT)

  1. Mar 17, 2004 #1
    Last year I indicated on this forum that some work by Reginald Cahill of Flinders University in Australia had found that Newton's theory of gravity, and Einstein's as well since it is tied to Newton's in the low velocity limit, were both limited to occasions of spherical symmetry. He found extra NGT terms. These terms explained why dark matter is not observed in spherical galaxies, but is observed in spiral galaxies using ordinary symmetric Newtonian theory. The bottomline of Cahill's result is that dark matter does not exist. It's just a theoretical fluke.

    The responses on this forum could not decide if Cahill was a fluke or the theory was.

    Now I have found, again on the Cornell archives, a recent paper by John Moffat of the University of Toronto, who independently claims that NGT eliminates the need for both dark energy and dark matter. Of course that raises the problem of how the universe could be flat, as established by many independent observations. But nevertheless, we now have two physicists arriving at the same conclusions, more or less, without referencing the other, seemingly independent of the other. I do not understand GR math. So I hope someone else could review these papers for us. The abstracts for the archives and links to the papers follow:

    Modified Gravitational Theory as an Alternative to Dark Energy and Dark Matter
    Authors: J. W. Moffat
    Comments: 17 pages, no figures, LaTex file
    The problem of explaining the acceleration of the expansion of the universe and the observational and theoretical difficulties associated with dark matter and dark energy are discussed. The possibility that Einstein gravity does not correctly describe the large-scale structure of the universe is considered and an alternative gravity theory is proposed as a possible resolution to the problems.
    Full-text: PostScript, PDF, or Other formats
    http://arxiv.org/abs/astro-ph/0403266




    Gravitation, the 'Dark Matter' Effect and the Fine Structure Constant
    Authors: Reginald T. Cahill (Flinders University)
    Comments: 11 pages, 3 eps figures
    Subj-class: General Physics
    Gravitational anomalies such as the mine/borehole g anomaly, the near-flatness of the spiral galaxy rotation-velocity curves, currently interpreted as a `dark matter' effect, the absence of that effect in ordinary elliptical galaxies, and the ongoing problems in accurately determining Newton's gravitational constant G_N are explained by a generalisation of the Newtonian theory of gravity to a fluid-flow formalism with one new dimensionless constant. By analysing the borehole and spiral galaxy data this constant is shown to be the fine structure constant alpha=1/137. This formalism then also explains the cause of the long-standing uncertainties in G_N and leads to the introduction of a fundamental gravitational constant G not = G_N with value G=(6.6526 +/- 0.013)x 10^-11 m^2s^{-2}kg^{-1}. The occurrence of alpha implies that space has a quantum structure, and we have the first evidence of quantum gravity effects.
    Full-text: PostScript, PDF, or Other formats
    http://arxiv.org/abs/physics/0401047
     
  2. jcsd
  3. Mar 17, 2004 #2
    John Moffat has been pushing NGT for about 30 years, at least. The main problem with the theory is that the metric is really not non-symmetric. Otherwise I suppose it's a realistic model...
     
  4. Mar 17, 2004 #3
    Non-symmetric gravitational theory

    "John Moffat has been pushing NGT for about 30 years, at least. The main problem with the theory is that the metric is really not non-symmetric. Otherwise I suppose it's a realistic model..."

    Nice to know he is ahead of Cahill. Could you explain how John's theory is not non-symmetric? BTW, he was a consultant of mine at MIT when he was at U. of Michigan almost 40 years ago.
     
  5. Mar 17, 2004 #4
    Re: Non-symmetric gravitational theory

    I meant that there is no reason for a spacetime metric to be non-symmetric. Moffat's is, of course. I suppose some confirmation will come if we ever observe dipole gravitational radiation (one of the NGT predictions).

    To be blunt: I see no reason for there to be a non-symmetric metric, and in fact there is lots of reason to assume it isn't.

    I didn't know John was at Michigan. He's been at Toronto for as long as I can remember (although now he's at the Perimeter Inst. in Waterloo, working on variable speed of light ideas).
     
  6. Mar 18, 2004 #5
    NGT

    It seems I do not know what you mean by 'metric'. Now some galaxies are spherically symmetric and some are spirals. Do they have different metrics? That kind of galactic symmetry or lack thereof seems to be what both Moffat and Cahill mean by non-symmetric gravitational theory. But I do not understand Moffat. Cahill is much more understandable.
     
  7. Mar 18, 2004 #6

    selfAdjoint

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    The original nonsymmetric theory of gravity was Einstein's unified field theory. There has recently been some progress in this.
     
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