I’m no mathematician, but I do like knowing that there are mathematical explanations for such small, quotidian occurrences as a shell buckling toilet paper roll.
Nice and unexpected example of buckling in an axially loaded cylinder. The load had probably been applied accidentally to this roll of toilet paper … There is a mathematical explanation for this buckling phenomenon.
2007, Geertje Hek
I saw this photo of a toilet paper roll with “shell buckling” patterns last year on the Shell Buckling website.
At the time, I was researching aluminum cans with similar patterning (See: Pseudo-Cylindrical Concave Polyhedral Packaging)
Geertje Hek is a Swiss mathematician, now teaching at the Institut International de Lancy. The website where she originally posted the photo is no longer up, but I was lucky this morning to have found it still available on the Internet Archive “Wayback Machine.”