Globular clusters as a probe for Weyl Conformal Gravity
  Eventual flattening of velocity dispersion profiles of some galactic globular
clusters in the Milky Way cannot be explained in the framework of Newtonian
gravity and hence in general theory of relativity in the weak field limit,
without resorting to the occurrence of tidal effects. We explore the
possibility of explaining such deviation from expected Keplerian fall-off in
dispersion profiles within the context of Weyl conformal gravity. We choose a
set of 20 globular clusters for which recent kinematic measurements are
available. We model the globular clusters with approximate Hernquist mass
profiles and choose a constant mass-to-light ratio throughout the cluster as
the only free parameter in the model. Our analysis finds reasonable Weyl
gravity fits to the observed dispersion profiles, exhibiting both Keplerian
decline and eventual flattening, with acceptable mass-to-light ratios. We
further recover a Tully-Fisher like scaling relation in globular clusters
through Weyl gravity.
