Gauge fields, ripples and wrinkles in graphene layers
  We analyze elastic deformations of graphene sheets which lead to effective gauge fields acting on the charge carriers. Corrugations in the substrate induce stresses, which, in turn, can give rise to mechanical instabilities and the formation of wrinkles. Similar effects may take place in suspended graphene samples under tension. 
F. Guinea, B. Horovitz, P. Le Doussal