FDG RESULTS FOR THE MILKY WAY GALAXY

The Milky Way (MW) is a barred spiral galaxy that includes our Solar System and is part of the Local Group of galaxies. Our home galaxy has a strong central bulge component and a dominant stellar disk at larger distances. FDG results for the MW are described in the figure below: the top panel shows the variable dimension D(R) (red-solid/red dashed curves) computed with the main NFDG model, and the mass-dimension function D_m(R) (blue-dashed curve), computed with the NFDG field equation. Both dimensions decrease from D=3.0 at smaller radial distances to D=2.2-2.4 at larger distances.

This is typical FDG behavior for galactic structures dominated by a spherically-symmetric component, such as the galactic bulge. Bottom panel: NFDG galactic rotation curves compared with two sets of experimental data (Sofue and Sylos Labini). There is perfect agreement between the main NFDG D(R) curves (red-solid/red-dashed) and the experimental data. This shows that, if our galaxy behaves as a fractal structure whose dimension D follows the red-solid/red-dashed curves in the top panel, then the resulting NFDG circular velocity curves in the bottom panel (red-solid/red-dashed) will perfectly fit the experimental data, without any need of dark matter. The NFDG D_m(R) curve (blue-dashed) is less effective in fitting the experimental data (Sofue only), but still a reasonably good fit.

A bulge-dominated galaxy, such as the MW, is characterized by a fractional dimension which is larger than the D=2 value that we observed for a disk-dominated galaxy, such as NGC 6503. This is due to the spherical symmetry of the dominating bulge component (see also similar galaxies in the NFDG catalog). The gas component is less important in this case. See my eight paper for a full discussion of this galaxy.