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I know most scientists, if not all scientists, believe Dark Matter cannot be accounted for by baryonic matter. And I don't mean baryonic matter that is unseen because it is not emitting light, I mean the baryonic matter we can see. Maybe regular matter only expresses 1/6th of its gravitational mass locally by the 1/R2 law but 6/6th starting a thousand light years away by the 1/R or similar law. How would scientists go about testing or eliminating such a hypothesis?