The maximum number of times a piece of paper has ever been folded in half is 11, thanks to my boys Adam and Jamie. https://partsolutions.com/the-law-of-seven-is-it-impossible-to-fold-paper-in-half-more-than-7-times/
this post was submitted on 04 Jan 2025
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There was a girl who folded a piece of paper in half 12 times in 2002... Link
I think she didn't fold it in half then half. Buy I'm not sure.
She did, after deriving the formula for the needed paper size. Also, the Mythbusters seemed to have used a steamroller, so I wonder if it was still a folded piece of paper, or more a block of paper similar to how damascus steel is made.
I like the part where it shatters/explodes.
Fun fact: if you do that 42 times, the piece of paper will be so thick it will reach the moon
At some point the thickness of the stack will exceed both the width and breadth of the "faces" of the paper, at which point you seriously have to consider in which dimension the folds should continue.
1mm * 2^42 = 4'398'046.511104 km
Distance to moon: 405'500km
I'm sorry I ever doubted you. I shall immediately undo my downvote.
What kind of upside down ass country/region uses apostrophes for thousands separator?
Very sorry for you you aren't able to handle swiss supremacy 😞😞😞
I'll pray for you 😞😞😞
Sweden does. As we use a comma (,) to separate units from decimals instead of a dot. It's annoying. Some programs like Excel freaks, and wolfram alpha thinks you're using coordinates.
That would most probably be Switzerland. Perhaps a referendum can be set up to change that?
Actully no. A referemdum can only be taken against a law by the Government, meaning to stop a change and Not to cause one.
There is the initiative, but it can only change the constitution, not laws itself.
Took the words out of my mouth but you were way more diplomatic
"the fuck is this shit?"
Australia?
1mm thick is no longer in the realm if paper but into some form of heavy cardboard. That said, even at .05mm, its still a pretty think wad when folded up.
I love this fact so much, because it always blows your mind.
I didn't start the day expecting to have the experience of suddenly wondering why I'd never thought before about the question of how many times you'd have to fold a piece of paper in half before you got a black hole and then knowing the answer in about three seconds, but given that I did it's no surprise that it's due to xkcd.
Help, halfway through folding my paper turned into nitrogen!
Keep folding until you hit Fe or Ni.
Huh, I've always thought that a black hole required a lot of mass, not just a lot of density. Apparently not true?
They can be any mass, it's density that matters. The smaller ones will not do much damage before they evaporate.
Well, a black hole with the mass of an A4 page is gonna evaporate almost instantly, turning all of that mass into energy. Those 5 grams will give you about a 100 kT explosion.
That's...... a lot of energy from so little mass
~~I think that might be an underestimate. Mass and energy should be conserved, so if the entire black hole evaporates the total energy output should be E = mc^2^. An A4 page has a mass of 6.25g. c is the speed of light, 299,792,458m/s.~~
~~0.00625kg * (299,792,458m/s)^2^ = 561,721,986,710,511.025J~~
~~The explosion of 1 metric ton (1000kg) of TNT is considered to be equivalent to 4,184 Joules. So 100KT = 418,400,000J. That's not close at all, we're gonna need more TNT:~~
~~561,721,986,710,511.025J / 4,184J/ton of TNT = ~134,254,776,938 tons of TNT.~~
~~Rounding off to significant figures, we're looking at 134 gigatons of TNT. For comparison, the Tsar Bomba, the most powerful nuclear weapon ever tested, had a yield of 50-58 megatons. That's somewhere in the neighborhood of 2,500 Tsar Bombas!~~
~~Maybe this paper folding experiment should be performed away from anything that might be damaged by the explosion. Like, uh, inhabited continents.~~
As pointed out below, I biffed the joules-per-ton-of-TNT thing, sorry!
I think your conversion is off. There's 4,184 joules per gram of TNT, not per ton (https://en.m.wikipedia.org/wiki/TNT_equivalent). Your calculation is off by six orders of magnitude. The first poster's calculation is correct.
Oh damn I think I read this:
The ton of TNT is a unit of energy defined by convention to be 4.184 gigajoules (1 gigacalorie),[1] which is the approximate energy released in the detonation of a metric ton (1,000 kilograms) of TNT.
And immediately brain farted "gigajoule" to "kilojoule." Thanks!
Like, uh, inhabited continents.
Make it inhabited planets. But you can stop at planets, no need to search for a new solar system.
AFAIR it follows E = mc^2, so even 5 grams will give you quite a boom.
That gives me an idea for a sci-fi weapon. It squeezes a few grams of stuff into an unstable black hole, which then releases all of the energy in a massive explosion.
If there was a compression ray, it could cause a few pico grams of matter to form a black hole on the surface of the target. If you pulse it very quickly, you get the appearance of a continuous cutting beam. Obviously, those explosions would be very loud and they would emit lots of radiation, so maybe it could be a tank mounted weapon.
They might do damage when they evaporate, though, due to the energy release
Hawinking radiation does a lot more damage the smaller a black hole gets
The DoD: So you're telling us we should research a black hole bomb?
180 or 50
Guess it’s "180 or so times", but it really looks like 50
you are of course correct
A little known fact: if you were able to fold a paper sheet in half 24 times, it would become wider than the whole known universe, and thicker than your mom’s ass