“Immovable object” vs. “unstoppable force” – which wins?

I was doing good following along with the logic behind this until the last line then – MIND BLOWN.

• Honyant

He lost me when he suggested that you can move an object by moving yourself because of relativity, but didn’t apply the same reasoning to accelleration.

I’m too tired to come up a with a good refutation, though I will point out that it really doesn’t matter either way. If we use his definition of an unstoppable force being an object that can’t have its acceleration altered, using your idea that acceleration is relative to the viewer would have no impact on anything else he said.

For instance, if you try to argue that you could simply change your own acceleration to change its, then it was never truly an unstoppable object in the first place, now was it (in fact, that’s essentially his argument for why an unmovable object cannot exist, which, as he pointed out, is the same thing as an unstoppable force)? In which case you haven’t satisfied the conditions presented. And if you skipped that argument, then everything else he’s proposed would still apply in the same way it always did.

More or less, either neither can exist, in which case it doesn’t matter, or both can exist, in which case it’d play out exactly as he said at the end.

• Luke

Relativity doesn’t apply to acceleration, because acceleration occurs due to a force being applied to something. That’s why, when you fly away in a space ship and come back to earth, you’ve experienced a different time amount of time passing by then the people remaining on earth; you accelerating away from earth is not the same as the earth accelerating away from you.

• Steven Fisher

I think the last line is a nice nod to a shift to fantasy due to the very nature of the question. Or, if you prefer, the impossibility of the last statement calls back to the impossibility of the original question.

• ProfX

Pffft. The correct answer is obviously: Hulk wins.

• Domicinator

I love physics. I never understood the math all that well, but I love the theories. I took advanced Physics in HS just because I loved talking about time travel and relativity and stuff.

• jtr3

Did not see that last line coming. Awesome!