A worm inside a head of cabbage can learn a lot by looking around. From the curvature of the surrounding leaves, it can get a good sense of how far it is from the center of the cabbage, and from the leaves’ orientation, it can figure out which direction provides the shortest route to the surface. A worm within a crumpled ball of paper is not so lucky: No simple local measurement of the surrounding layers points the way out of the ball or suggests how far the journey might be. That’s what Dominique Cambou and Narayanan Menon, of the University of Massachusetts Amherst, found in their three-dimensional structural study of highly crumpled sheets.1
Crumpled sheets of paper are a familiar form to most of us, but they still hold many secrets. (See the article by Michael Marder, Robert Deegan, and Eran Sharon in PHYSICS TODAY, February 2007, page...
