The title of this piece refers to Seurat's painting, Sunday Afternoon on the Island of the Grande Jatte (1884-6). At the time that Seurat introduced Pointillism, physicists were hotly debating whether matter was continuous or atomic. Though hypothesized by the ancient Greeks, the existence of atoms was firmly established at the beginning of the twentieth century (see Pollen for more of this story).
This piece was created by a computer program that simulated the motion of circular atoms, producing this snapshot of their positions (for you physics types, the Metropolis algorithm was used to produce a state in the microcanonical ensemble for a periodic system of hard disks). The colors and positions are purely random, with the constraint that atoms cannot overlap, yet our brains automatically organize the visual field into patterns so you will probably see "constellations" of atoms.
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