A DERIVATION OF MODIFIED NEWTONIAN DYNAMICS

Modified Newtonian Dynamics (MOND) is a possible solution for the missing mass problem in galactic dynamics; its predictions are in good agreement with observations in the limit of weak accelerations. However, MOND does not derive from a physical mechanism and does not make predictions on the transitional regime from Newtonian to modified dynamics; rather, empirical transition functions have to be constructed from the boundary conditions and comparisons with observations. I compare the formalism of classical MOND to the scaling law derived from a toy model of gravity based on virtual massive gravitons (the graviton picture) which I proposed recently. I conclude that MOND naturally derives from the graviton picture at least for the case of non-relativistic, highly symmetric dynamical systems. This suggests that - to first order - the graviton picture indeed provides a valid candidate for the physical mechanism behind MOND and gravity on galactic scales in general.