I think this would result in a reverse-Newton’s First Law.
As it turns out, the object does move.
Give an example.
You can bet as sure as you live
Something’s gotta give, something’s gotta give,
Something’s gotta give.
I thought the Big Bang was how Jesus was conceived? 
Har…
I’m guessing the unstoppable force gets re-vectored in a direction away from the immovable object? ala wind going around a mountain? or am I not getting the question? Perhaps the unstoppable force transfers THROUGH the immovable object via the 8th dimension? By way of Planet Ten?
The unbreakable analogy shatters.
I’m reminded of that time that Buckaroo Banzai, using his oscillation overthruster, drove right through a mountain.
The universe would be recreated. With pie.
Cottleston Cottleston Cottleston Pie,
Why does a chicken? I don’t know why.
Ask me a riddle and I reply
Cottleston Cottleston Cottleston Pie.
—Winnie-the-Pooh
Well, the unstoppable force has dibs. Duh.
Now, you could have made it a trick question by saying “what happens when an immovable object runs into an unstoppable force”, because immovable objects don’t run into things…
What happens when an unstoppable force meets an immovable object?
I don’t think you need to worry about it all that much. I mean the chances of it actually happening are like a 1000000 to 1.
What happens when an unstoppable force meets an immovable object?
XTC’s Skylarking.
At least that’s how it was characterized in the book Chalkhills and Children. Andy Partridge being the unstoppable force and Todd Rundgren being the immovable object.
At least that’s how I remember it from reading it in a bookstore many years ago.
My semi-serious answer is that if you have a universe with both an unstoppable force and an immovable object, they cannot interact with each other. That is, the force merely passes through the object as if it wasn’t there.
You don’t say. :dubious:
So, what’s the “one official answer” that you were thinking of?
The unstoppable force passes through the immovable object and continues.
Oh well, that’s what you get when you get a phone call in the middle of posting and then don’t go back to check if your point has been made in the meantime.
Well its only “official” in the sense that it was the correct answer in the book.
Anyway all these smartarses “Oh, thats obvious, its simple!” still haven’t got it so I’m not giving it away!
What happens is the force isn’t stopped and the object doesn’t move. 
On a serious note, does a “force” necessarily move objects? Maybe it’s just not that kind of a force, so there’s no contradiction.