The latest blog post at Triton Station doesn't disappoint. It makes two main points.
First, the MOND predictions, which are far more detailed than those of dark matter theories, accurately note the subtle twists and turns of gravitational effects corresponding to different distributions of ordinary matter that shouldn't exist in a dark matter theory. The observation that every detail of ordinary matter is reflected in dark matter phenomena is known as Renzo's Rule.
Second, in the vertical direction relative to the galactic disk in the Milky Way, gravity appears to be Newtonian and not naively MONDian. In other words, MOND effects are only seen in the radial direction.
This implies an underlying theory with qualitative features similar to Deur's GR-SI, in which MOND effects involve dimensional reduction of gravitational fields as a second order effect that fades with distance more slowly than Newtonian gravity. Even if he theory does not flow directly from conventional general relativity as claimed, his work's predictions hold up.
2 comments:
could Gravitational force distribution in fractal structures explain MOND in one direction and Newton in another
https://www.researchgate.net/publication/1840875_Gravitational_force_distribution_in_fractal_structures
"We study the (newtonian) gravitational force distribution arising from a fractal set of sources.
We show that, in the case of real structures in finite samples, an important role is played by morphological properties and finite size effects.
For dimensions smaller than d-1 (being $d$ the space dimension) the convergence of the net gravitational force is assured by the fast decaying of the density, while for fractal dimension D>d-1 the morphological properties of the structure determine the eventual convergence of the force as a function of distance. We clarify the role played by the cut-offs of the distribution. Some cosmological implications are discussed.
Comment: 9 pages, latex, 2 postscript figures, also available at http://www.phys.uniroma1.it/DOCS/PIL/pil.html Accepted for Publication in Europhysics Letters. Minor modifications added"
Far from the worst paper you've found. One of Deur's big conceptual leaps that is often missing in the gravity in astronomy contexts is the importance of the shape of the matter distribution.
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