Testing Weyl gravity at galactic and extra-galactic scales

  title={Testing Weyl gravity at galactic and extra-galactic scales},
  author={Koushik Dutta and Tousif Islam},
  journal={Physical Review D},
We examine the viability of Weyl conformal gravity as an alternative to the general theory of relativity. By using the extended rotation curve of the Milky Way and velocity dispersions of four globular clusters, we show that Weyl gravity predictions without resorting to dark matter comply with observations at the galactic scale. For the Milky Way, we demonstrate that the uncertainty in baryonic modeling results in a bracket of possible rotational velocities which well encompasses the diversity… Expand

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