The Secret Life of Chaos (BBC documentary)

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35 points·KonaB··5 comments

This is an excellent program, but I dislike that the presenter and one of the interviewees both say that chaotic systems are "inherently unpredictable". Chaotic (classical) systems are deterministic, so the same initial conditions will always give you the same result.

What makes them chaotic is that they are exponentially sensitive to initial conditions (i.e. "the butterfly effect"). This means that a difference that might go undetected in the initial condition can cause a potentially large change to the final result.

True, but if it's impossible to measure the initial conditions to the necessary degree of accuracy, then it is quite legitimate to describe the system's behavior as "unpredictable."

Yes, but describing it as "inherently unpredictable" gives the impression that you could take one of the simple equations that are chaotic and do things like produce truly random numbers on your computer. This is not the case.

"Chaos is one of the most unwelcome discoveries of science." (the video, Part 3/6, cca 7:10)

Why are the still saying that? When I first read about deterministic chaos in the James Gleick book [1], I almost wept with joy and awe. It opened my eyes and made complete sense.

[1] Chaos: Making a New Science (http://en.wikipedia.org/wiki/Chaos:_Making_a_New_Science)

It makes sense in the background of a clockwork universe that the video was going on about - it was a kick in the pants to a whole lot of rigid thinking. A bit of hyperbole, but it apparently rocked the scientific boat.

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