1. If there was such thing as an immovable object, then there could not be a force that could push it. If there was such thing as a unstoppable force, then there will be no object that it can't move. So the two can't coexist together.
2. If an object is unmovable, it would have to have an infinite mass to overcome inertia. Besides for this being impossible, if an object did have an infinite amount of mass, it would collapse under its own gravity, creating a black hole.
3. In order to have an unstoppable force, you would need an infinite amount of energy, and there isn't an infinite amount of energy in the universe.
So, reasons 2 and 3 say that it can't happen in out world, and reason 1 says it can't happen even theoretically, because you are creating two rules that contradict each other.
I agree with gunthex if there was a unstopable force other than gravity it could go through the inmoveable object. But we have not found an inmoveable object. The earth moves, air moves, mountains move, the galaxy moves. There is nothing know to man (or at least me) that can't be moved
I say both forces negate each other. The object is immovable, right? So it will oppose any force by it's exact counterforce. The unstoppable object flying towards the immovable object has a force that, if opposed, will raise until it is stronger that the opposing force, or else it wouldn't be unstoppable, right? That just means that the force coming from both objects, being opposed, will go on raising until it is too much and probably crushes both objects... or, if the objects are unbreakable, the force will never stop raising. ...wait, that means, to us it would seem as if the unstoppable force is sticking to the immovable object, thus apparently (but only apparently) not moving anymore.
