Evidence for descrete space and no dark matter

[yanniru]

I am not sure what forum category this should go in, but since Cahill's paper (see abstract and link below) claims to be the first evidence for discrete space, which of course supports LQG, this may be the appropriate location. I searched the Physics Forum for Cahill and got zero hits. His theory is rather groundbreaking if true.



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

 

[meteor]

The mine/borehole g anomaly refers to an experiment made in a mile- deep borehole in Greenland that seems to contradict Newton's law of gravity. You can read about it here: http://www.totse.com/en/fringe/gravity_anti_gravity/weighty.html

 

[marcus]

Nereid's comments on the claimed deficiency of dark matter in elliptical galaxies would be most helpful, I imagine.

My impression was that dark matter is needed to explain NOT ONLY the flat rotation curves of spiral galaxies, but also the fact that clusters of galaxies (including ellipticals) can stay bound, given the high observed random velocities of individual galaxies).

Nereid knows a lot about the evidence for dark matter.

Cahill's idea has some potential weakness. It seems to call for a preferred frame (the CMB frame) and an idea of absolute motion. (Is this your impression also? I was not sure.)

His revision of Newtonian gravity also calls for a dimensionless constant which is 139 based on Greenland ice borehole measurements and 137 based on spiral galaxy
arguments, and Cahill makes the leap of identifying this with the 137.036... of electrodynamics---the inverse fine structure constant. But he does not offer an explanation, at least that I can see in this paper, for why his gravity constant should be the same as the fine structure constant (which is about the strength of electrical attraction, a coupling constant for electrical charge, not about gravity
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But one can say seveal things in Cahill's defense. He has been published elsewhere. And he has done research and dug up evidence of unexpected deficiency of dark matter in ellipticals, and gravitational anomalies under Greenland ice. Here are prior publications:

R.T. Cahill, Quantum Foam, Gravity and Gravitational Waves, in Relativity, Gravitation, Cosmology, pp. 168-226, eds. V. V. Dvoeglazov and A. A. Espinoza Garrido
(Nova Science Pub., NY, 2004).

he cites this preprint http://arxiv.org/physics/0312082

R.T. Cahill, Gravity as Quantum Foam In-Flow, Apeiron, 11, No.1, pp. 1-52(2004).

R.T. Cahill, Absolute Motion and Gravitational Effects, Apeiron, 11, No.1, pp. 53-
111(2004).

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Here is a sample of his evidence for dark matter deficiency:

[5] A.J. Romanowsky, et al., A Dearth of Dark Matter in Ordinary Elliptical Galaxies,
Science 301, 1696(2003).

[7] K.C. Freeman, The Hunt for Dark Matter in Galaxies, Science 302, 1902(2003).

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If Nereid deigns to comment, it will be to murder Cahill but in a nice way, I expect

Maybe the cutting edge of science is so mixed up with its fringe
that you can never say confidently which is which,
and what makes it real science instead of pseudo
is not its normality or craziness but
the fact that it makes predictions by which it risks
empirical negation.