I have read that the strength of the strong interaction between two quarks is roughly the same as the weight of a 10 tonne truck (i.e. 105 N). There is a relationship between Force and distance and work and energy and mass (and I am aware of the extent to which Newtonian mechanics is perturbed by special relativity in all this), and it seems to me, looking at the sums, that my introductory sentence above may just be the logical/mathematical restatement of ‘E=mc2’. However, E=mc2 – and the whole of special relativity in fact - seems to me to just be a brilliant restatement of the statement “the speed of light is a constant” (or “there is no such thing as the ether”). An (admittedly not comprehensive) Internet search seems to indicate that much of the information about the strong force is inferred theoretically rather than directly measured. Is our whole theory about the strong force and its magnitude resting just on the foundations of Maxwell and Michelson and Morley, and their findings about the significance, and invariance, of the speed of light?