Let us note in passing that it would not be the first time that the kinetic action would be modified as special relativity does just this too, changing for a single particle mv2∕2 → − mc2γ−1 in Skin (where ∘ --------- γ(v) = 1∕ 1− (v∕c)2), leading for a moving body to a redefinition of the effective mass as meff = mγ(v). With this analogy in mind, a rather simplified view of the Lorentz-breaking modification of inertia needed in order to reproduce MOND would be that meff ≃ m μ(a), where a is the amplitude of the acceleration with respect to an absolute preferred inertial frame.