WAS FEYNMAN WRONG? - RESTURY OF THE SPAGHETTI BREAK EXPERIMENT

Spaghetti is a staple delight, both delicious and robust. When we grasp each end of a dry spaghetti strand and forcefully bend it towards the center, it typically shatters into three, four, five, or more pieces, but seldom just two. Intrigued by why spaghetti often breaks into several fragments rather than two, Nobel Prize-winning physicist Richard Feynman famously spent an evening in his kitchen breaking spaghetti strands, yet he couldn't provide a satisfactory explanation. The fracture process of dry spaghetti happens in a mere instant, under 30 milliseconds, making it challenging to observe with the naked eye or analyze quantitatively.　　In this paper, we present a device specifically designed to break dry spaghetti, utilizing a high-speed camera to explore the statistical behavior of spaghetti fracture under various parameters. We capture the intricate details of the fracturing process. Interestingly, the fractures in dry spaghetti do not occur simultaneously. Initially, a fracture at a single point causes a sudden change in curvature, triggering a vibrational wave that increases local curvature elsewhere along the strand. When the curvature at any point reaches a certain threshold, fractures occur at multiple points. Moreover, the number of segments into which the spaghetti breaks correlates with the bending speed. Notably, our observations reveal that spaghetti frequently breaks into two pieces, contradicting Feynman's and other previous observations.