In an interesting (and highly interactive) talk, van Acoleyen (Durham) showed that certain modifications to gravity (or, in Dvali's terminology, certain scalar-field interactions with the graviton) can plausibly lead to a MOND-like gravitational force law on scales the size of galaxies and acceleration on scales the size of the Universe, with Newtonian gravity on all scales where measurements are precise and unassailable. Though it is in some absolute sense unlikely to be correct (indeed, it has some fine-tunings), and though it might not reproduce the CMB and growth of structure (the calculations had not been done), it is a reminder that the "dark matter" might one day be obviated by a new conception of gravity. Might.
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