Couldn’t resist this, although it’s purely link propagation. If you don’t know who Claude Shannon is, this might not be so exciting. But the excellent blog collision detection has a post on juggling as a physical Turing test, which links to a wonderful short piece of video showing Shannon first juggling, then demonstrating his own juggling robot, “W.C. Fields”. As a juggler and computer scientist myself, it’s wonderful to see that one of the greats has devoted so much attention to the art.

Actually, following the link trail a bit further I found Arthur Lewbel’s obituary for Shannon (the source of the movie), with many juggling references and the following statement of Shannon’s “Juggling Theorem”:

(F+D)H=(V+D)N, where F is the time a ball spends in the air, D is the time a ball spends in a hand, V is the time a hand is vacant, N is the number of balls juggled, and H is the number of hands. Which just goes to show, no matter how anchored in the real world a mathematician might seem to be, the lure of generalisation just can’t be ignored. Number of hands?!?