No. 99: May-Jun 1995
R. Feynman carried out spaghetti experiments but did not deign to theorize on why he almost always ended up with three pieces each time he attempted to break a piece in two. Fortunately for science, O. and R. Nickalls have come up with an answer.
"We can only assume that Feynman was not really trying, since when we investigated this profound and fundamental problem in our own kitchen laboratory, not only did we quickly establish the underlying mechanism, but we even went on to formulate the following general rule for linear spaghetti structures:- If a spaghetti stick is uniformly bent until it fractures and ejects a third piece, then the third piece is always ejected outwards from the convex side.
"When the spaghetti fractures for the first time, the two remaining pieces then spring outwards, and providing there is a sufficiently weak potential fracture site on the opposite side a second fracture occurs, resulting in a third piece being ejected away from the initially convex side."
(Nickalls, Oliver and Richard; "Linear Spaghetti," New Scientist, p. 52, 1995)
Comment. We have omitted the mathematical analysis of this complex phenomenon because it involves tensor analysis!