The Lorenz butterfly is significant becasue it illustrates the concept of "sensitive dependence upon initial conditions."
In the 1960's the American meteorologist Edward Lorenz (NOT Lorentz!) discovered, more or less by chance, that the mathematical models for the weather system were extremely sensitive to the initial conditions.
Small changes in these initial conditions result in big effects. Of course this had long been known as "popular wisdom"...:-), but now it was shown that this deterministic chaos was a result of the non-linearity of the underlying differential equations. As a result long-term weather predictions are impossible.
In 1972 he presented a talk with the title:
Predictability: Does the Flap of a Butterfly’s Wings in Brazil set off a Tornado in Texas?
This butterfly image has become a very popular one and you can find it in almost any of the hundreds of Internet sites about Chaos Theory....【阅读全文】