this post was submitted on 02 May 2025
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xkcd

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Title text:

Unstoppable force-carrying particles can't interact with immovable matter by definition.

Transcript:

[An arrow pointing to the right and a trapezoid are labeled as 'Unstoppable Force' and 'Immovable Object' respectively.]
[The arrow is shown as entering the trapezoid from the left and the part of it in said trapezoid is coloured gray.]
[The arrow is shown as leaving the trapezoid to the right and is coloured black.]
[Caption below the panel:] I don't see why people find this scenario to be tricky.

Source: https://xkcd.com/3084/

explainxkcd for #3084

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[–] [email protected] 10 points 3 weeks ago (9 children)

Pretty sure none of these exist so idk why it bothered any1 in the first place.

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[–] [email protected] 21 points 3 weeks ago (1 children)
[–] [email protected] 11 points 3 weeks ago (6 children)

so if god creates rock so heavy that it can't lift it, its hand just passes through the rock? makes sense.

[–] [email protected] 11 points 3 weeks ago (1 children)

A rock so heavy you cannot lift it is not an immovable object. Just cause you are weak does not mean you are right.

[–] [email protected] 6 points 3 weeks ago (1 children)
[–] [email protected] 15 points 3 weeks ago (3 children)

Dear God,

A rock so heavy you cannot lift it is not an immovable object. Just cause you are weak does not mean you are right.

Kind regards, me

[–] [email protected] 12 points 3 weeks ago* (last edited 3 weeks ago) (1 children)
[–] [email protected] 5 points 3 weeks ago

Joke’s on you, old man! I have a chariot of iron!

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[–] [email protected] 10 points 3 weeks ago* (last edited 3 weeks ago) (6 children)

I think if God creates a rock so heavy he can't lift it, it's probably a black hole. By definition we can't know what happens inside a black hole, because no information escapes the event horizon. As it's now consistent with known physics that we can't know many aspects of this interaction between God and the black hole, I think this paradox is basically solved. We don't know any more about the interaction, but it's no longer a paradox, it's consistent with physics.

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[–] [email protected] 6 points 3 weeks ago (2 children)

God is distinct from the creation and has no physical shape inside the creation so the idea of "object too heavy to lift" is already conceptually nonsensical.

But also in the scope of our physics: What would an object be that is too heavy to "lift" for anyone and anything? It would be the heaviest object in the universe. So what will happen with the heaviest object in the universe? It would be the main center of gravity for everything else. In the same way you cannot "lift" the earth, but rather lift yourself from it as your force will just propel you away from the earth rather than the earth away from you, while you are inside the area dominated by earths gravitational field.

[–] [email protected] 2 points 3 weeks ago

nothing is distinct from xkcd, if it exists there is an xkcd about it

[–] [email protected] 7 points 3 weeks ago* (last edited 3 weeks ago) (1 children)

When you jump you are pushing the earth away from yourself a little bit, and then some of your gravity pulls the earth back toward you. You have moved the earth, and for a brief moment your jump has in fact altered Earth's orbit.

[–] [email protected] -1 points 3 weeks ago (2 children)

Relative to the sun, which is the next center of gravity. As you go up the chain you end up with the heaviest object which you cannot move relative to anything, as it is the logical point of relative movement for everything else.

[–] [email protected] 3 points 3 weeks ago (1 children)

You need to be thinking about n-body physics though, everything affects everything. If the earth moves, that moves the sun a little, if the sun moves, that moves the local cluster a little, etc. Why wouldn't that affect this heaviest object?

I mean, are you suggesting that this heaviest object is simply the center of the universe and that all coordinates are defined around it? Because while that seems practical, I don't think it's how matter and space interact.

[–] [email protected] 1 points 3 weeks ago (1 children)

The universe is expanding everywhere all at once in all directions. So space itself is "moving". It is impossible to define movement except relative to another object made from matter.

[–] [email protected] 3 points 3 weeks ago (1 children)

Ok, I think we're on the same page here. But I'm still not sure about one of your previous comments, you suggested that this "heaviest object" can't move because it would be the logical reference to which any other body is measured.

But I want to think about that a bit. Let's say this heaviest object (HO) has something orbiting it and we're looking at it from earth with a telescope. As the smaller body orbits, we would probably see this HO wobble, right? Meaning that even if it's the most massive thing around, it's still affected by other objects, it can be moved.

[–] [email protected] 1 points 3 weeks ago

That is a good question. I have to think about it.

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[–] [email protected] -2 points 3 weeks ago (3 children)

No that doesn't make sense. The thing you're alluring at is a classical thought experiment showing contradiction in allmightiness.

P1: God is Almighty, meaning he can do anything

Therefore he must be able to create a stone he can't lift. But then there is something he can't do: Either he can not lift the super stone, or he can not create a super stone that he can't lift.

[–] [email protected] 1 points 3 weeks ago

An omnipotent and omniscient being would have the ability to change words definitions or logic. They cant be stopped with a logical contradiction

[–] [email protected] 6 points 3 weeks ago* (last edited 3 weeks ago) (1 children)

lol I am not alluring to anything I am just giving a xkcd twist to this well known paradox

[–] [email protected] 4 points 3 weeks ago (1 children)
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[–] [email protected] 3 points 3 weeks ago (3 children)

Is Randall now just retelling YouTube videos from 2013? https://www.youtube.com/watch?v=9eKc5kgPVrA

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[–] [email protected] 6 points 3 weeks ago (1 children)

So who would win in a fight between the Juggernaut and the Blob?

[–] [email protected] 4 points 3 weeks ago* (last edited 3 weeks ago)

That has been debated to death before and it obviously depends on the writer and version of the characters, but in most cases neither are fully immovable or unstoppable. If they were, Juggernaut would probably just be redirected and keep going.

A little more practically speaking, Juggernaut wins easily:

  • The Blob is a mutant who can basically lock himself to the ground with a short distance around him and become immovable in relation to the ground while being able to absorb most impacts to effectively eliminate the force experience by him and thus the ground.

  • The Juggernaut is not a mutant, but an avatar of Cyttorak the Destroyer, the God/Demon ruler of the Crimson Cosmos dimension. He can tap into more and more of that power to the point where he can fight a somewhat angry Hulk on almost equal ground(he's even defeated him with some help).

Even if you let Blob be immovable and able to ignore all kinetic force, he still has a big weakness: He's not very superhuman when it comes to other forms of damage, or just pain in general. As demonstrated when he tried to go after one of the intelligent versions of Hulk. Hulk realized he couldn't move or hurt him, so he grabbed his stomach and started pulling. It quickly hurt so much that he instinctively stopped anchoring himself to the ground. At which point he basically became an invincible bouncing ball since he can't attach to the air. SoHulk treated him as one, until he sent him flying by using a big metal girder as a bat. And it's important to note that Blob is not very strong or good at fighting when it comes to superhumans, since he basically just relies on his powers.

And to expand on the Crimson Cosmos: It is so powerful that Doctor Strange taps into it to contain Hulk. It's even used to contain Thanos with most of the stones in the MCU(The red cloth strips that hold him is a spell called the "Crimson Bands of Cyttorak")

[–] [email protected] 64 points 3 weeks ago (5 children)

Facepalm Man i'm dumb, this is a great answer to that thought experiment.

[–] [email protected] 3 points 3 weeks ago

Eh, it's just redefining the assumed meaning. "Intangible" does mean "unstoppable" in a way, but that's not really what's intended.

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