Toward a Symmetrization of Gravity I. Classical Formulation: Results and   Predictions; Dark Matter With a Difference
  We propose an additional term in the classical gravitational force law, which is repelling in nature, and which may solve the dark matter problem. As an inverse cube field interaction, it operates over 4 real spatial dimensions and its effect on our observable 3-D space may account both for flat rotation curves and standard Newtonian dynamics at small radial distances. By utilizing cosmological clustering scales, we can derive the universal interaction strength, and show that this naturally leads to an altered Planck mass that becomes the neutron/proton rest mass. Moreover, the correct value for the electron rest mass can be predicted using only classical electrostatics coupled with the current theory. On cosmological scales, the interaction easily accounts for the acceleration of the Hubble flow. 
Terry Matilsky