ORDER AND DISORDER IN FLUID MOTION

The development of complex states of fluid motion is illustrated by re viewing a series of experiments, emphasizing film flows, surface waves , and thermal convection. In one dimension, cellular patterns bifurcat e to states of spatiotemporal chaos, In two dimensions, even ordered p atterns can be surprisingly intricate when quasiperiodic patterns are included, Spatiotemporal chaos is best characterized statistically, an d methods for doing so are evolving, Transport and mixing phenomena ca n also lead to spatial complexity, but the degree depends on the signi ficance of molecular or thermal diffusion.