WEBVTT

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Ever since the Big Bang, the electrons inside every atom have been revolving their orbits

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for 15 billion years, yet never colliding with each other.

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Who maintains such an order within such a small realm?

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Yeah, so when we think about the electrons going around the atoms, this is actually one

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of the things that historically persuaded people that quantum mechanics was true.

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Because if you think of the electron as just this little billiard ball orbiting around the

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nucleus, sort of like the way the Earth orbits around the sun, the problem with that is as

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the electron moves, it would be radiating energy away, and eventually it would lose all of

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its energy, and it would fall into the nucleus and crash.

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So just if we have a satellite around the Earth, none of them stay up there forever.

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They all eventually run out of energy and fall down and burn up in the atmosphere.

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So there was a big question in people's minds, why doesn't that happen with the electrons orbiting

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the atoms?

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And the answer turns out to be quantum mechanics, that the lowest resonance of the electron around

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the atom has a certain wavelength, and it corresponds to a certain distance of the electron away

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from the nucleus.

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And it simply can't go any lower.

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So in sort of a musical analogy, you could say, if I'm playing a musical instrument, there

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is one lowest note that I can play on that musical instrument, and I can't go any lower.

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And we would call that the fundamental resonance, and something very much like that with the

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electrons around the atoms.

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So you could say that the system of quantum mechanics keeping the electrons stable is really

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another place where God intervenes to make the laws of physics work so that things allow

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us to exist and so on.

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If it was a purely classical world, then actually we couldn't exist because the electrons would

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just fall into the nuclei.

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And again, when we talk about fine tuning parameters, one of the parameters that is extraordinarily

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important is Heisenberg's, or sorry, the Planck constant, which determines the length scale

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over which that quantum mechanics applies.

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And if that was too large, then we would have really weird quantum mechanical effects, and

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if it was too small, then other bad things would happen.

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And so quantum mechanics actually is another example of a fine tuned theory that allows things

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to be stable.