connecting the classical and the quantum

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Working in a cramped MIT laboratory in 1961, meteorologist Edward Lorenz stumbled upon a new science. Wanting a closer look at the data of a weather simulation he was running, Lorenz restarted it in the middle. Within a few minutes, everything changed and the data he had expected to see had morphed into strange new patterns. A stunned Lorenz checked his inputs. He had rounded the starting values by about .0001, which should have been insignificant. And yet it was not. At the time, scientists thought small changes in starting values should make only a small difference in most systems. But sometimes such tiny shifts will cause a very different outcome, completely out of proportion with the size of the change—this hypersensitivity to initial conditions is what Lorenz dubbed the “butterfly effect” and what we now call chaos. Chaos, which underlies systems as diverse as fractals, ferns, and weather, causes behavior so complex and unexpected that, though it is fundamental to the natural order, it was only recently that scientists began to characterize it. Chaotic movement is unstable and unpredictable, but completely deterministic, meaning that it’s controlled by its starting conditions.

more from Veronique Greenwood at Seed here.