This video is about chaos theory and the butterfly effect.
From the Massachusetts Institute of Technology in the USA:
April 16, 2008
Edward Lorenz, an MIT meteorologist who tried to explain why it is so hard to make good weather forecasts and wound up unleashing a scientific revolution called chaos theory, died April 16 of cancer at his home in Cambridge. He was 90.
A professor at MIT, Lorenz was the first to recognize what is now called chaotic behavior in the mathematical modeling of weather systems. In the early 1960s, Lorenz realized that small differences in a dynamic system such as the atmosphere–or a model of the atmosphere–could trigger vast and often unsuspected results.
These observations ultimately led him to formulate what became known as the butterfly effect–a term that grew out of an academic paper he presented in 1972 entitled: “Predictability: Does the Flap of a Butterfly’s Wings in Brazil Set Off a Tornado in Texas?”