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18.4. The butterfly effect and the birth of chaos theory

In a seemingly stable system, a tiny, marginal event can suddenly upset the balance, so development takes an unexpected, dramatic direction.

In 1961, mathematician Edward Lorenz worked at the Massachusetts Institute of Technology on the east coast of the United States to model a weather system with twelve different variables. He had at his disposal an LGP-30 computer with less capacity than a music Christmas card has today.

It took an infinitely long time.

He had run a full round of simulations and found that he wanted to take a closer look at a limited part by running just this one again. To save time, he took the key number from a specific time, fed it into the machine and started from there.

The poor machine, consisting of a few thousand radio tubes and diodes, could deliver numbers with six-digit accuracy. But on the printout he sat with, this was rounded to three decimal places. 0.506127 was printed as 0.506, with which he started the next run.

The result was highly unexpected. By changing a single number only slightly, the development of the weather became radically different than in the first simulation.

He had discovered the butterfly effect.

If a butterfly in the jungle of Brazil flaps its wings, it could result in a tornado over Texas in the United States a few weeks later. That's how it was presented to the public. Microscopic changes anywhere in a complex, dynamic system can have extreme consequences for further development.

It was named chaos theory.

The word butterfly effect was allegedly launched by Lorenz at a conference in 1972, eleven years after its discovery. The word chaos theory is said to have been uttered for the first time at a conference in December 1977.

It's pure young science.

One often says that the 20th century gave us three scientific revolutions: quantum mechanics, Einstein's theories of relativity – and chaos theory.

«Chaos» does not mean that everything is chaos.

It is a condition we do not understand, but it is not without legality. The word is Greek and does not mean disorder at all, which has its own word; «tarakhe».

Chaos, on the other hand, for the Greeks, was the great emptiness, the potential that existed before the cosmos, which is thus chaos in realised form.

The gods shaped chaos with their will to what we all wander around in, the universe.

That is how the Greeks thought, to the extent that we know what they were thinking.

From the 17th century, these nuances are forgotten, and chaos is chaos.

Then came the chaos theory, the complexity theory.

What does it say?