The physicist Eric J. Heller’s Transport XIII (2003), inspired by electron flow experiments conducted at Harvard. According to Heller, the image ‘shows two kinds of chaos: a random quantum wave on the surface of a sphere, and chaotic classical electron paths in a semiconductor launched over a range of angles from a particular point. Even though one is quantum mechanical and the other classical, they are related: the chaotic classical paths cause random quantum waves to appear when the classical system is solved quantum mechanically.’