From furrowed brows to mountain-forming ripples in Earth's crust, wrinkles are ubiquitous. To better understand these widespread phenomena (SN: 6/15/96, p. 376), scientists would like to predict certain topographical properties of wrinkles, such as the heights of their folds and how close together those folds lie.
A simple new theory does just that. In the Feb. 21 Physical Review Letters, Enrique Cerda of the University of Santiago in Chile and Lakshminarayanan Mahadevan of the University of Cambridge in England mathematically analyze wrinkles. They report a straightforward relationship between elasticities of materials and the topographies of the wrinkles that form in them.