The dynamics of three nearby E0 galaxies in refracted gravity
  We tested whether refracted gravity, a theory of modified gravity that
describes the dynamics of galaxies without the aid of dark matter, can model
the dynamics of the three massive elliptical galaxies, NGC 1407, NGC 4486, and
NGC 5846, out to $\sim$$10R_{\rm e}$, where the baryonic mass component fades
out and dark matter is required in Newtonian gravity. We probed these outer
regions with the kinematics of the globular clusters provided by the SLUGGS
survey. Refracted gravity mimics dark matter with the gravitational
permittivity, a monotonic function of the local mass density depending on three
parameters, $\epsilon_0$, $\rho_{\rm c}$, and $Q$, which are expected to be
universal. Refracted gravity satisfactorily reproduces the velocity dispersion
profiles of the stars and red and blue globular clusters, with stellar
mass-to-light ratios in agreement with stellar population synthesis models, and
orbital anisotropy parameters consistent with previous results obtained in
Newtonian gravity with dark matter. The sets of the three parameters of the
gravitational permittivity found for each galaxy are consistent with each other
within $\sim$2$\sigma$. We compare the mean
$\{\epsilon_0,Q,\log_{10}\left[\rho_{\rm c}\left(\mathrm{g}\,
\mathrm{cm}^{-3}\right)\right]\} = \{0.089^{+0.038}_{-0.035},
0.47^{+0.29}_{-0.21}, -24.25^{+0.28}_{-0.20}\}$ found here with the means of
the parameters required to model the rotation curves and vertical velocity
dispersion profiles of 30 disk galaxies from the DiskMass Survey (DMS):
$\rho_{\rm c}$ and $Q$ agree within 1$\sigma$ with the DMS values, whereas
$\epsilon_0$ agrees within 3$\sigma$. This agreement suggests that ellipticals
and disk galaxies allow for common values of the parameters of the permittivity
and supports the universality of the permittivity function.
