Are Galactic Rotation Curves Really Flat?

In this paper we identify an apparently previously unappreciated regularity in the systematics of galactic rotation curves; namely, we find that at the last detected points in galaxies of widely varying luminosity, the centripetal acceleration is found to have the completely universal form ( v 2 / c 2 R ) last = γ 0 /2 + γ* N */2 + β* N */ R 2 , where γ 0 and γ* are new universal constants, β* is the Schwarzschild radius of the Sun, and N * is the total amount of visible matter in each galaxy. This regularity points to a possible role for the linear potentials associated with conformal gravity, with the galaxy-independent γ 0 term being found not to be generated from within individual galaxies at all but rather to be of cosmological origin, being due to the global Hubble flow of a necessarily spatially open universe of 3-space scalar curvature k = -(γ 0 /2) 2 = -2.3 × 10 -60 cm -2 .