Dark Matter Strikes Back
  Mc Gaugh et al. (2016) have found, by investigating a large sample of
Spirals, a tight non linear relationship between the total radial acceleration,
connected with the Dark Matter phenomenon, and its component which comes from
the distribution of baryonic matter, as the stellar and HI disks. The strong
link between these two quantities is considered by them and by other
researchers, as challenging the scenario featuring the presence of DM halos in
galaxies. Or, at least, to indicate the peculiar nature of the underlying dark
matter particles. We have explored this issue by investigating a larger number
of galaxies by means of several techniques of analysis. Our results support and
even increase, both qualitatively and quantitatively, the validity of McGaugh
et al. (2016) 's relationship. However, we prove that such relationship exists
also in the scenario featuring dark matter halos + ordinary baryonic matter and
that it arises by the fact the DM is less concentrated than the luminous matter
and it is progressively more abundant in lower luminosity objects. These
properties are due to well known astrophysical effects: the implications of
this relationship for the properties of dark matter halos are nothing of new or
of unexpected. The relationship, definitively, is not a portal to go beyond the
standard picture of $\Lambda$CDM galaxy formation.
