this post was submitted on 02 May 2025
836 points (98.3% liked)

xkcd

10717 readers
270 users here now

A community for a webcomic of romance, sarcasm, math, and language.

founded 2 years ago
MODERATORS
 

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

top 50 comments
sorted by: hot top controversial new old
[–] jecxjo@midwest.social 19 points 2 days ago

i think I've made that game engine before.

[–] Hamartiogonic@sopuli.xyz 34 points 3 days ago* (last edited 3 days ago) (6 children)

Maybe the universe will crash due to division by zero, floating-point error, integer overflow and segmentation fault, all of them occurring simultaneously. The objects will experience infinite velocity and infinite forces, there will be rounding errors, the system will run out of RAM and storage space. The universal CPU will max out all threads, and run out of cooling capacity. The hardware catches fire, the entire universe immediately collapses into a singularity, resulting in a new big bang as the system reboots. Oh, and the log files are corrupted, so good luck troubleshooting that one.

[–] gnufuu@infosec.pub 19 points 3 days ago (1 children)

A popup will appear asking you to buy the "Extended Physics" DLC

[–] Hamartiogonic@sopuli.xyz 6 points 3 days ago (1 children)

First billion years free. After that it’s 17.99 per millennia.

[–] lud@lemm.ee 6 points 2 days ago (1 children)

What currency?

I doubt the universe accepts Euro or whatever.

[–] noxonad@lemmy.world 8 points 2 days ago

It's just 17.99. Take it or leave it.

load more comments (5 replies)
[–] Goretantath@lemm.ee 63 points 3 days ago (5 children)

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

load more comments (5 replies)
[–] LovableSidekick@lemmy.world 15 points 3 days ago* (last edited 3 days ago)

Noooooo! You're violating my binary thinking! Either A or B has to win!

[–] AmidFuror@fedia.io 65 points 3 days ago (8 children)

The expression as I heard included "an irresistible force."

[–] SGG@lemmy.world 85 points 3 days ago (2 children)

That's on the nsfw version of xkcd

[–] Tudsamfa@lemmy.world 1 points 2 days ago

"And irresistible is what I am, baby!"

load more comments (6 replies)
[–] SkunkWorkz@lemmy.world 20 points 3 days ago (1 children)
[–] argarath@lemmy.world 8 points 3 days ago

Dammit I should have posted my exact same solution back when I thought of it for the first time, but I was lazy so eh my fuck up

[–] Charlxmagne@lemmy.world 9 points 3 days ago (6 children)

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

[–] pyre@lemmy.world 7 points 2 days ago

if people only bothered to think about things that exist (especially things that they think exist) we would probably go the way of the dodo. funnily enough that would prevent the dodos from going that way but whatever.

I highly recommend watching the Vsauce video on supertasks—it's a great video as expected from Vsauce but also ends on a great note about people and their tendency to think about things like this.

[–] Smokeydope@lemmy.world 9 points 3 days ago* (last edited 3 days ago) (1 children)

There are some pretty close physical analogs that are fun to think about. You cant move a black hole by exerting physical force on it in the normal way so practically infinite gravity wells are like a immovable "object", though if you're sufficently nerdy enough you can cook some fun ways to harness its gravitational rotation into a kind of engine, or throw another black hole at it to create a big explosion and some gravitational waves which are like a kind of unstoppable force moving at the speed of light.

[–] turtlesareneat@discuss.online 6 points 3 days ago

Relevant username

You can attract a black hole using gravity tho

[–] Harvey656@lemmy.world 6 points 2 days ago (1 children)

You clearly haven't met my mother.

[–] lugal@sopuli.xyz 2 points 2 days ago (1 children)

Is the an unstoppable force or an immovable object or a little bit of both?

[–] AA5B@lemmy.world 5 points 2 days ago

Neutrinos are pretty close to an unstoppable force: they can pass right through the earth without being stopped.

I believe this is an expectation of dark matter, to being even closer to an unstoppable force. Perhaps a reason we haven’t found it yet would a because we don’t have a detector that can stop it

[–] Hamartiogonic@sopuli.xyz 5 points 3 days ago* (last edited 3 days ago)

These kinds of contradicitons exist in man made structures, such as laws, rules and regulations. In situations like that, a judge has to pick which rule to follow and which one to ignore. The first time that happens, it becomes the standard solution (precedent) for those kinds of problems.

load more comments (1 replies)
[–] ianhclark510@lemmy.blahaj.zone 27 points 3 days ago (1 children)

"What happens when an unstoppable force meets an immovable object?" that image doesn't show a force meeting an object

[–] BartyDeCanter@lemmy.sdf.org 132 points 3 days ago (6 children)

They met, they just didn’t interact. Kinda like me at a work party.

load more comments (6 replies)
[–] billwashere@lemmy.world 6 points 2 days ago
[–] iAvicenna@lemmy.world 11 points 3 days ago (19 children)

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

[–] Gladaed@feddit.org 11 points 3 days 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.

[–] iAvicenna@lemmy.world 6 points 3 days ago (1 children)
[–] traceur301@lemmy.blahaj.zone 15 points 3 days 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

[–] SkyezOpen@lemmy.world 12 points 3 days ago* (last edited 2 days ago) (1 children)
[–] humorlessrepost@lemmy.world 5 points 3 days ago

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

load more comments (2 replies)
[–] Cocodapuf@lemmy.world 10 points 3 days ago* (last edited 3 days 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.

load more comments (6 replies)
load more comments (17 replies)
load more comments
view more: next ›