The Curious Case of Evenly Breaking Spaghetti
Twist and Bend: The Secret to break spaghetti in even halves

Pasta is the epitome of a heartwarming, easy-to-cook meal. However, one variant of pasta, spaghetti, is infamous for being too long to fit into a pan of boiling water. While the easiest solution would be to break the spaghetti in half, it’s never a straightforward process, as an attempt to break it in even halves resulted in uneven, multiple broken bits. The question has forever intrigued scientists and was considered a wacky daily life problem that physics just couldn’t answer. Only recently, two MIT mathematicians have found out how to break a strand of spaghetti in equal halves – by simply applying a twist while bending it.

Renowned American physicist, Richard Feynman, is one the many scientists to have been bamboozled by this enigma. Danny Hillis, a supercomputer pioneer, and Feynman’s colleague, have elaborated in his biography the conundrum that both scientists faced one night while preparing spaghetti for dinner. He reports that Feynman noticed that the dry noodle always broke in three or more pieces when it was snapped. As dinner waited, the duo broke several strands of the noodle trying to come up with crazy theories of why it happened. At the end of the discussion, they were unable to come up with any good ones, instead having a kitchen floor full of broken spaghetti noodles to clean up.

The reason why spaghetti didn’t encounter a clean break when snapped, was finally solved in 2008 by French scientists Basile Audoly and Sebastien Neukirch. The duo discovered that when even pressure is applied to both ends of a thin long object, the force creates a “snapback effect”. The initial break releases a wave of energy that propels other sections of the object to fracture as well. For this discovery, the duo was awarded the Ig Nobel Prize, a parody award intended to “honor the imaginative” and “celebrate the unusual”.

While the reason behind why thin noodles broke in uneven halves was discovered, another question still remained – so how does one break a strand of pasta in equal halves. The problem was taken up by two MIT graduate students, Ronald Heisser and Edgar Gridelloas, as part of the final project for their physics class. The duo broke several strands of pasta over the course of three months in their lab, ultimately devising a one-of-a-kind spaghetti breaking contraption. Using a high-tech camera to capture up to a million frames per second, the duo studied the process in great detail. Finally, they fit the process on a mathematical model, which eventually allowed them to achieve the breakthrough.

They found out that all that was required to perfectly halve spaghetti is to twist the strands (270 to 360 degrees) while bending it. By twisting and bending, the stress placed on the object being broken is distributed – weakening the “snapback effect” and allowing the pasta to release energy while it unwinds, thus preventing more fractures. Vishal Patil, a third student involved in the experiment, says, “In our study, we go a bit further and show that actually you can control this fracture cascade and get two pieces if you twist it, instead of many, many pieces.” The finding is set to be published in the Proceedings of the National Academy of Science (PNAS) journal.

While the mystery of how not to spill bits of spaghetti on your kitchen floor has been resolved, the finding has several widespread applications. The study has demonstrated one of the ways to control fracture, usually a “chaotic and random” process. Patil added, “Just understanding these complex fracture systems would be interesting going forward as well, as there’s still a lot to be discovered about fracture control, and this is an example of fracture control.”