Dark Matter: a Challenge to Standard Gravity or a Warning?

Abstract

We suggest that the conventional need for overwhelming amounts of astrophysical dark matter should be regarded as a warning to standard gravity rather than as merely a challenge to it, and show that the systematics of galactic rotation curve data can just as readily point in the direction of the equally covariant conformal gravity alternative. In particular we identify an apparent imprint of the Hubble flow on those data, something which while quite natural to conformal gravity is not at all anticipated in the standard gravitational paradigm.