Why does a zebra have stripes?  How can the Great Red Spot of Jupiter
persist for centuries in the strongly turbulent fluid?  This talk addresses
such difficult questions in a general way: why do patterns form in systems
that are driven away from thermodynamic equilibrium?  Systems in nature and
industry are driven away from equilibrium by gradients, for example,
gradients in temperature, velocity, or concentration.  For a sufficiently
small gradient, no pattern will form; any spatial variations in the
properties of a system will correspond simply to those of the system's
boundary. However, when a gradient is increased beyond a critical value,
spatial patterns spontaneously form; examples include stripes, squares,
hexagons, and rotating spirals.  The principles of pattern formation
phenomena will be illustrated with examples from   physics, chemistry, and
biology.
 
 

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