Spontaneous buckling of elastic sheets with a prescribed non-Euclidean metric

We present an experimental study of the three-dimensional (3D) configurations that result from non-uniform lateral growth/shrinking of thin elastic sheets. We build gel sheets that undergo inducible differential shrinking. The non-uniform shrinking prescribes a non-Euclidean metric on a disc, and thus a non-zero Gaussian curvature. To minimize their elastic energy the free sheets form three-dimensional structures that approximate the imposed metric. We show how both large scale buckling and wrinkling-type structures can be generated, depending on the nature of possible embeddings of the imposed metric in Euclidean space. (c) 2007 Elsevier B.V. All rights reserved.