Slide 1
Òenergy condensationÓ in matter
Elastic focusing: sharp structure from smooth forcing
Singularities in thin sheets  I
Conditions for crumpling: thin elastic manifold
Bending vs stretching when thickness h ¨ small
Confining an unstretchable object
When does curvature create stretching in d dimensions?
For what dimensions does confinement make vertices? ridges?
Isometric (unstretchable) limit accounts for singularities
Slide 11
Energy of an isolated vertex is logarithmic
Òkite shapeÓ explains emergent width scale w of ridge
numerics confirm scaling of curvature profile with thickness
virial theorem confirms stretching-bending competition
implications of stretching ridges
growth of ridge energy with opening angle a
Induced edge singularities
Induced edges are weaker than real ridges
Unstretchable d-cone: sets stage for d-cone puzzles
D-cone core: what limits the focusing?
Simulation tests scaling of Rc
Slide 23
Gaussian charge optimisation confirms ridge scaling
Curvature constraints from Gauss Bonnet theorem