Sandpiles

	The identity for a 50x50 grid graph created using 2-photon lithography then imaged using an scanning electron microscope. Its size is approximately half the width of a hair. (Created by Joy Perkinson.)
	Close-up of the above.
	Another close-up.
	Identity on the Klein bottle grid graph with a single sink. Created in 3D using Bryan Head's GSoC application. With his application, one may rotate the images.
	The maximal stable configuration plus the identity configuration in the process of stabilizing. (Again using Bryan Head's application.)
	The identity element on a torus grid graph with one sink.
	Same as above but in 3D.
	The identity element on a torus grid graph in which each vertex has an out-edge to the north and east and an in-edge from the south and west.
	Same as above but in 3D.
	Identity on a hex grid with sides of length 12. Each vertex has degree 6.
	Identity on a hex grid with sides of length 14.
	Identity on a hex grid with sides of length 29.
	Identity on an aztec diamond graph.
	Four million grains of sand dropped a single vertex on an infinite grid and allowed to settle. High resolution. (Thanks to Seth Terashima.)
	Guess!
	Identity elements for sandpiles on a grid with evolving boundary (thanks again to Seth.)
	Identity for the 20x20 grid graph.
	Art? (These are created using Bryan Head's application.)

Gallery