| This talk will describe three recent experiments on emergent patterns
in three diverse physical systems. The overall shape and subsequent
rippling instability of icicles is an interesting free-boundary growth
problem. It has been linked theoretically to similar phenomena in
stalactites. We attempted to grow ideal icicles and determine the
motion of their ripples. Washboard road is the result of the
instability of a flat granular surface under the action of rolling
wheels. The rippling of the road, which is a major annoyance to
drivers, sets in above a threshold speed and leads to waves which
travel down the road. We studied these waves, which have their own
interesting dynamics, both in the laboratory and using 2D molecular
dynamics simulation. A viscous fluid, like syrup, falling onto a
moving belt creates a novel device called a "fluid mechanical sewing
machine." The belt breaks the rotational symmetry of the rope-coiling
instability, leading to a rich zoo of states as a function of the belt
speed and nozzle height.
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