Editing 3033: Origami Black Hole

{{comic
| number    = 3033
| date      = January 3, 2025
| title     = Origami Black Hole
| image     = origami_black_hole_2x.png
| imagesize = 272x480px
| noexpand  = true
| titletext = You may notice the first half of these instructions are similar to the instructions for a working nuclear fusion device. After the first few dozen steps, be sure to press down firmly and fold quickly to overcome fusion pressure.
}}

==Explanation==
{{incomplete|Created by an ORIGAMI FUSION REACTOR TRYING DESPERATELY TO BE A BLACK HOLE - Please change this comment when editing this page. It needs an explanation for the title text. Do NOT delete this tag too soon.}}

This comic shows what at first appears to be an actual page of {{w|origami}} directions, like [https://origami.me/crane/ this one] or [https://origami.guide/origami-animals/origami-rabbits/origami-sleeping-rabbit/ this one], except labeled "How to fold a real origami black hole". However, it quickly devolves into nothing other than repeating folds in half. This wouldn't really create a black hole,{{citation needed}} but it would get very difficult, nearly impossible, long before the 190 folds in half that the instructions require.

This comic is likely a reference to the [https://en.wikipedia.org/wiki/Schwarzschild_radius Schwarzschild radius] of a piece of paper. The Schwarzchild radius is a characteristic of every object that depends on the object's mass. If an object is compressed into the volume of a sphere with its characteristic Schwarzschild radius, then that object will become a black hole. (More specifically, it will become a [https://en.wikipedia.org/wiki/Schwarzschild_metric Schwarzschild black hole].) As such, if a piece of paper were folded sufficiently many times so as to fit within its own Schwarzschild radius, it would become a black hole. However, this would require compressing the paper into a flat sheet at every step, otherwise the paper would have a thickness greatly exceeding its Schwarzschild radius.

If we assume standard [https://en.wikipedia.org/wiki/Origami_paper kami origami paper] with a side length of 15cm and a weight of 70 grams per square meter, we get a Schwarzschild radius of 2.339×10^-30 meters corresponding to a mass of 1.575 grams. It follows that, ignoring the paper's thickness, we would need to halve each side length -log_2((2×2.339×10^-30)/0.15)=94.69 times to fit each side length within the "Schwarzschild diameter" of the paper. Using the square folding technique in the comic, this would take approximately 95*2=190 steps to complete, the exact number given in the comic.

In actual fact, it's not possible to fold a piece of paper this many times, because you can't compress it enough. For an ordinary letter-sized sheet (A4 or 8.5x11) the maximum number of folds is 7. The world record for the total number of folds is 12, done with a length of tissue paper 3/4 mile long.

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}

:How to fold a '''''real''''' origami black hole:

:Step 1.
:[A square sheet of paper shown folded in half, with a dashed line going across the middle, and an arrow pointing from one half to the other.]

:Step 2. 
:[Folded in half again]

:Step 3.
:[Folded in half again]

:Step 4.
:[Folded in half again]

:Step 5.
:[Folded in half again]

:Step 6.
:[Folded in half again]

:Step 7.
:[Folded in half again]

:Step 8.
:[Folded in half again]

:Step 9.
:[Folded in half again]

:Steps 10-189.
:[Text shown between tall square brackets:]
:Fold paper in half another 180 or so times.

:Step 190.
:[A labeled arrow points to a dot]
:Black hole!

{{comic discussion}}

[[Category:Physics]]