It was a puzzle that drove noted physicist Richard Feynman to spend an entire evening on it: Why can't you break dry spaghetti into just two pieces?
If you try it for yourself, you'll see — it's not going to break cleanly into two pieces. You're likely to have at least three pieces. Feynman reportedly spent an evening breaking dry spaghetti in his kitchen trying to figure out why the noodles wouldn't snap in two.
The 2006 winners of the Ig Nobel award, Basile Audoly and Sebastien Neukirch of the Université Pierre et Marie Curie, in Paris, were able to explain why it breaks into more than two pieces. It's because if you bend the spaghetti noodle at the middle in an attempt to break it, it creates a vibration that runs along the entire noodle strand. (You can see an animation of a breaking noodle in slo-mo here.)
But can you ever successfully break a noodle in two pieces? A new MIT study says yes — you have to twist it:
In a paper published this week in the Proceedings of the National Academy of Sciences, researchers report that they have found a way to break spaghetti in two, by both bending and twisting the dry noodles. They carried out experiments with hundreds of spaghetti sticks, bending and twisting them with an apparatus they built specifically for the task. The team found that if a stick is twisted past a certain critical degree, then slowly bent in half, it will, against all odds, break in two.
Graduate students working on a final project in a class for professor Jörn Dunkel came up with the idea.
Dunkel told MIT News that the students tried a manual test and figured out you have to twist — but it requires a really strong twist.
So student Ronald Heisser built a machine to twist and bend the noodles.
When the noodle is twisted and then bent, the vibration that causes the noodle to break is lessened by the twist. The twist-back releases energy from the noodle and prevents any additional fractures, Dunkel told MIT News.
“Once it breaks, you still have a snap-back because the rod wants to be straight,” Dunkel explained. “But it also doesn’t want to be twisted.”