
MIT mathematicians solve age-old spaghetti mystery - denzil_correa
http://news.mit.edu/2018/mit-mathematicians-solve-age-old-spaghetti-mystery-0813
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deburo
Odd, I saw that spaghetti phenomenon on smartereveryday just a few days ago,
but it appears it was posted in 2014. Heh.

[https://www.youtube.com/watch?v=ADD7QlQoFFI](https://www.youtube.com/watch?v=ADD7QlQoFFI)

Anyway, very cool.

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semi-extrinsic
I don't get how this is an interesting result. When you are allowed to change
the applied stress (not just simple bending), getting it to break into just
two pieces is easy.

By holding the spaghetti with two fingers at each end and applying compression
together with bending, i.e. making the spaghetti look kinda like a sine wave
from bottom to bottom, I can break spaghettis into just two pieces with
success rate well above 50%. And I have confirmed with simple bending of
shorter spaghettis that it's not just because of a shorter effective length.

Here's a picture of five spaghettis broken into just two pieces, along with
one unbroken for comparison:

[https://imgur.com/a/gOTiHG3](https://imgur.com/a/gOTiHG3)

Now I gotta explain to my wife why there are broken spaghettis.

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lsh
is that actually spaghetti though? it looks like linguine ...

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nosefrog
According to the article, the model doesn't apply to linguini, so I'm not
surprised it doesn't always break into 3+ pieces.

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phyzome
Ah, cool! I also wonder if the twisting stress means that the noddle breaks
before it is bent quite as far, which would also reduce the snap-back effect.

I also wonder if the twist-back breaks up the snap-back waves by redirecting
their momentum.

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iaw
Fun fact: when a cylindrical shaped object fractures from a twisting stress it
leaves 45 degree break patterns. Try it with a pencil.

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SquirrelOnFire
Depends on the material. Brittle materials will. Ductile materials tend to
break on a 90 degree plane -
[https://goo.gl/images/QYMJmf](https://goo.gl/images/QYMJmf)

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jgh
I guess I've never tried doing it one noodle at a time or something, cause
breaking a bunch of them at once results in them broken in two. Maybe they
prevent each other from snapping back enough to break again?

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smcl
I've never bothered to break them - why would you want tiny bits of spaghetti?
Also wouldn't noodles be something completely different - like when I think
"noodles" I think of an Asian dish, not a plate of spaghetti.

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sp332
It's called a "spaghetti noodle", like in the subheading of the article.

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TheRealPomax
*in the US (but not necessarily in other English speaking countries)

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bryanrasmussen
finally my code will be clean!

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mec31
Now if only someone could explain why toppled smokestacks break into three
pieces, my life would be complete :-)

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lurquer
I've been trying this all night, and I can't get any of them to break. Maybe I
overcooked it.

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TheRealPomax
Hm, it's interesting that this was unsolved for so long, given that any pasta
chef can teach you how to break spaghetti, fettucini, etc. in two by twisting
while bending. Very odd.

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Anon84
Not sure what the big deal is... this was solved back in 2005 in one of the
top physics journals
[https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.95...](https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.95.095505)

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bachmeier
FTA:

"Feynman’s kitchen experiment remained unresolved until 2005, when physicists
from France pieced together a theory to describe the forces at work when
spaghetti — and any long, thin rod — is bent. They found that when a stick is
bent evenly from both ends, it will break near the center, where it is most
curved. This initial break triggers a “snap-back” effect and a bending wave,
or vibration, that further fractures the stick. Their theory, which won the
2006 Ig Nobel Prize, seemed to solve Feynman’s puzzle. But a question
remained: Could spaghetti ever be coerced to break in two?"

