Astrophysical data analysis of the weak-field predictions support the claim
that modified gravity (MOG) theories provide a self-consistent,
scale-invariant, universal description of galaxy rotation curves, without the
need of non-baryonic dark matter. Comparison to the predictions of Milgrom's
modified dynamics (MOND) provide a best-fit and experimentally determined
universal value of the MOND acceleration parameter. The predictions of the
modified gravity theories are compared to the predictions of cold non-baryonic
dark matter (CDM), including a constant density core-modified fitting formula,
which produces excellent fits to galaxy rotation curves including the low
surface brightness and dwarf galaxies.
Upon analysing the mass profiles of clusters of galaxies inferred from X-ray
luminosity measurements, from the smallest nearby clusters to the largest of
the clusters of galaxies, it is shown that while MOG provides consistent fits,
MOND does not fit the observed shape of cluster mass profiles for any value of
the MOND acceleration parameter. Comparison to the predictions of CDM confirm
that whereas the Navarro-Frenk-White (NFW) fitting formula does not fit the
observed shape of galaxy cluster mass profiles, the core-modified dark matter
fitting formula provides excellent best-fits, supporting the hypothesis that
baryons are dynamically important in the distribution of dark matter halos.Comment: Ph.D. Thesis. 251 pages, 22 figures, 17 table
