The Stellate Chip

How an amoeba writes a route

The 64-lane stellate chip: a star-shaped disc with a central chamber holding the organism and sixty-four narrow lanes radiating outward in eight labelled sectors, one sector per city. An inset shows that a sector's eight lanes stand for the eight positions in the route. A second inset shows the feedback loop running from chip to camera to computer to projector and back.

The chip is a passive plate roughly the width of a coat button, cut from hardened photographic resin and coated with gold. It holds no circuitry. Its 64 lanes are eight cities by eight route positions, so a branch extended down the lane marked "city C, position three" asserts that C was visited third, and the organism's whole body is a route written in occupied lanes. Every six seconds a camera photographs the disc, a program recalculates which lanes to discourage, and a projector lights them. Nothing in the loop is alive except the organism in the middle.