The result of this is that, according to general relativity, when dealing with very large scales, the traditional Newtonian idea of "inertia" does not actually apply, and cannot necessarily be relied upon.
The result of this is that, according to general relativity, inertia is the gravitational coupling between the matter and the spacetime. When dealing with very large scales, the traditional Newtonian idea of "inertia" does not actually apply, and cannot necessarily be relied upon.