Until recently, scientists lumped systems into three categories: 1) periodic, settling down to a regular oscillation; 2) stable, reaching a fixed value; or 3) unstable, shooting off to infinity. Unpredictable systems were called "random" or "noisy" and were thought to be combinations of the three different categories. But in 1962, Edward Lorenz made a world-view changing discovery while studying computerized weather simulation. His model followed a course that was neither random, periodic, nor convergent. The model exhibited very complex behavior, yet consisted of only a few simple equations. The curve generated by the model exhibited a bizarre characteristic; two points located close to one another on the curve (so close, in fact, that it would require a computer with impossibly infinite precision to differentiate between them) would inevitably take widely divergent paths. This observation led to the conclusion that long term weather prediction would never be possible. The Lorenz- Butterfly effect is often presented as an example of chaos: the tiny eddy currents produced when a butterfly flaps its wings can change the outcome of a hurricane. Scientists are using chaos as a new way to look at previously misunderstood phenomena, such as population curves, epidemiology, turbulence, heat flow, biological rhythmicity, and social and political movements.
"Chaos: The Making of a New Science," is an exciting account of the early days of this emerging new approach to systems dynamics. James Gleick's very readable text takes you inside the labs and research centers where chaos is being studied. This is a real "can't-put-it-down" science book. Rare indeed.
(M. Frauenfelder)
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Chaos: The Making of a New Science
James Gleick
Penguin Press, 1988
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To get his neat results, Galileo also had to disregard nonlinearities that he knew of: friction and air resistance. Air resistance is a notorious experimental nuisance, a complication that had to be stripped away to reach the essence of the new science of mechanics. Does a feather fall as rapidly as a stone? All experience with falling objects says no. The story of Galileo dropping balls off the tower of
Pisa. as a piece of myth, is a story about changing intuitions by inventing an ideal scientific world where regularities can be separated from the disorder of experience.
