Or, three or four or eight different dark matters (one of which is our stuff), that all only weakly interact with each other through gravity. Or, even more stra

Or, three or four or eight different dark matters (one of which is our stuff), that all only weakly interact with each other through gravity. Or, even more strangely, one of those dark matter's interacts with stuff that doesn't even interact with the gravitational field. A graph of weakly-connected physics.