Planar sheets meet negative curvature liquid interfaces
  If an inextensible thin sheet is adhered to a substrate with a negative Gaussian curvature it will experience stress due to geometric frustration. We analyze the consequences of such geometric frustration using analytic arguments and numerical simulations. Both concentric wrinkles and eye-like folds are shown to be compatible with negative curvatures. Which pattern will be realized depends on the curvature of the substrate. We discuss both types of folding patterns and determine the phase diagram governing their appearance. 
Zhenwei Yao, Mark Bowick, Xu Ma and Rastko Sknepnek
cond-mat.soft cond-mat.mtrl-sci