Abstract:
Spaghetti is a beloved and resilient staple, known for its deliciousness and robust texture. When dry spaghetti is forcefully bent towards the center by grasping each end, it often breaks into several pieces rather than just two, a phenomenon that intrigued Nobel Prize-winning physicist Richard Feynman. Despite spending an evening in his kitchen experimenting with spaghetti strands, Feynman was unable to provide a satisfactory explanation. The fracture process of dry spaghetti happens in a fraction of a second (under 30 milliseconds), making it challenging to observe with the naked eye or analyze quantitatively. In this paper, we introduce a device specifically designed to break dry spaghetti while capturing the fracturing process using a high-speed camera to explore the statistical behavior of spaghetti fracture under various parameters, revealing the intricate details of the process. Our observations show that fractures in dry spaghetti do not occur simultaneously. Instead, a fracture at a single point initiates a sudden change in curvature, which triggers a vibrational wave that increases the local curvature at other points along the strand. When the curvature at any point reaches a critical threshold, fractures occur at multiple locations. Furthermore, we find that the number of segments into which the spaghetti breaks correlates with the bending speed. Surprisingly, our observations reveal that spaghetti frequently breaks into two pieces, contradicting Feynman's and other previous findings.