[RightWhale]

If you are inside Einstein's famous falling room your local space will seem absolutely stationary and free of gravity. If the room is falling past you, the space inside will be moving while your own space will carry the gravitational field. Which is it? That is relativity.

[inquest]

Perhaps I'm missing some element, but is that along the same lines as saying that if two objects, in the absence of any gravity, pass each other in space, there's no absolute way of saying that one's stationary, and the other moving?