Why can’t the pasta break into two

  Feynman is a well-known American physicist. He has participated in the atomic bomb development project code-named “Manhattan Project”. He has solved numerous physical problems in his lifetime. He is the 1965 Nobel Prize winner in physics. However, an accidental discovery in his life puzzled him. Although he had been thinking for many years, he finally failed to solve the puzzle.
  One night, Feynman and his friends were so busy experimenting that they did n’t eat dinner. They were hungry. They decided to cook a bowl of pasta to make them hungry, and continued to work after eating. The kitchen has dried, thin, round and long pasta in case it is needed. While waiting for the water to boil, Feynman thought about what he had just done, while picking up a piece of pasta, holding the two ends of the pasta with both hands, and bending it to break. Originally an unintentional move, the result made him an unexpected discovery: the noodles did not break into two sections from the middle, but broke into three sections. Feynman was very strange, so he picked up another spaghetti and bent it, which was also broken into three sections. Why isn’t the pasta broken into two? Feynman intends to experiment a few more times. As a result, the remaining pasta has been tested one by one. Until a pack of pasta was completely folded, Feynman failed to break a pasta into two. Some of them are broken into three sections, and some are broken into four sections, but they are not broken into two sections.
  If you happen to have a bag of dried, thin, round and long pasta, you can also experiment. The cost of this experiment is not high, but it will make you discover the same as Feynman.
  A research team from France found that when the spaghetti is evenly bent from both ends to a certain degree, it will break near the middle, but this breakage will cause springback, thus generating a bending wave, triggering more fracture. They believe that this explanation can answer “Feynman’s question” well.
  A research team from the Massachusetts Institute of Technology recently attracted media attention. Because they found a way to break the spaghetti into two sections, and the process of breaking can be controlled. In order to conduct this research, they first conducted manual experiments and found that when the pasta was twisted to a certain extent and then folded in half, the pasta may break into two sections. To this end, they improved the experimental apparatus and specially manufactured a mechanical device. There is a clip on each end of this device, which can fix the two ends of the pasta. One side of the device can rotate, driving one end of the pasta to different angles, and the clip on the other side can slide forward to bend the pasta. They used this device to test hundreds of noodles, and used the camera to record the experiment at a rate of one million frames per second. The result of the experiment is: when one side of the pasta is twisted to close to 360 °, and then slowly bent and folded in half, the pasta can be broken into two pieces, and the results of the experiment are the same for the pasta of different diameters.
  Why is this so? The researchers conducted further research. They found that when bending a spaghetti, the rebound effect caused the spaghetti to vibrate repeatedly, which produced a bending wave, and the torsion also produced a torsion wave. The torsion wave propagates more than the bending wave. The speed is fast and consumes a part of the energy, thus avoiding the multiple spaghetti breaks. Obviously, this experiment is very helpful to study the stability of thin round rods.
  It is foreseeable: since the pasta can be broken from three to two sections, it may not break at all when the pasta is bent in the future. In other words, in the future, people may be able to find a new material, or use a method to make thin, round, and long-shaped objects more durable.
  It seems that there is learning everywhere in life. Observe carefully, think carefully, and this is how science advances step by step.