Another way to think of this is that spacetime has mass. Spacetime and dark matter are both referring to the same 'stuff'. The stuff is a supersolid that is dis

Another way to think of this is that spacetime has mass. Spacetime and dark matter are both referring to the same 'stuff'. The stuff is a supersolid that is displaced by ordinary matter. The Earth displaces the 'stuff'. The displaced 'stuff' pushes back. The displaced 'stuff' pushing back is gravity. Curved spacetime = Geometrical representation of gravity. Displaced supersolid dark matter = Physical representation of gravity.