One of the more convincing solutions has been proposed by Gary V. Smith of Aston University. He explained it as so:
“The initial step to answering the superficially paradoxical question of “What would happen if an unstoppable force met an immovable object?” is establishing what is meant by 'immovable'. In order for something to move, its position must be measured relative to something else that is not moving. The universe is expanding, with everything in the universe constantly travelling further from it's centre. If the immovable object were to remain stationary within space, it would be inherently be being moved by the universe, through it's expansion; if the immovable object were to counter act the movement of the universe by moving at an equal velocity through space in the opposite direction to the expansion, towards the centre of the universe, then the very idea (in the implied context of the question that the object is stationary) of it being an immovable object is invalidated because it is moving (towards the universe’s centre).
Therefore, the only possible answer as to the location of the immovable object is that it exists at the exact centre of the universe, where the expansion of the universe is negligible in its effect on the location of the object. It is worth noting that because the immovable object must be at the centre of the universe, there can never be more than a single immovable object at any one point in time.
The next step is to define what the force and object in question are comprised of. Some theories state that the immovable object is solid and merely deflects the unstoppable force. However, this theory collapses when the situation of an unstoppable force colliding with an immovable object at an exactly 90 degree angle to each other. If the object can deflect the force, then in this instance the force would rebound back into itself; it has clearly been stopped by