…atomic physics and in the hydrogen atom. And they have been given names by people. h squared over me squared has been called the Bohr radius. I've named these things so that you learn the words. When you read about them, you know what they are. And it…

…e to the minus rho. And therefore, the amplitude to be found at different radial distances, let's say in the scale of a Bohr radius, is an exponential. More likely to be found at the origin and less likely to be found further out. Just an exponential.…

…a number which comes up so often in the quantum mechanics. It's the unit of magnetic moment for atoms. It's called the Bohr magneton. This is called because it's a unit that's very convenient for magnetic moments in quantum mechanics. But we then have…

…and that light could be considered in certain ways. as the particles with energy h omega. And that by this time, Bohr had pointed out that any system, any system of atoms has energy levels not necessarily equally spaced like Planck's oscillator. And…

…constant so that this is a convention. Yeah. But this is a conventional arrangement. This particular distance is called Bohr's radius, the Bohr radius. And there's 0.528 times 10 to the minus 10 meters, or a half an angstrom. And that tells us that the…

…this. When the new quantum mechanics was discovered, the classical people, which was everybody else except Heisenberg and Schrodinger and Bohr and so on, they said, look, the theory isn't any good because you can't answer certain questions, like what's the…

…curve. The relative chance that you will find it in a certain vicinity is high near the nucleus. That doesn't sound like the Bohr atom, does it, where it said it was going around. The most likely place you'll find the electron is at the nucleus. And…

…like a donut edge on and a donut looking through the hole. That begins to look, of course, a little bit more like what Bohr was thinking when he said that a hydrogen atom is a nucleus with the electron going around. Lights, please. Well, I guess I…

…up to the neutron two possibilities existed one was the law of energy conservation is not right in fact it was proposed by Bohr for a while that maybe the conservation law worked only statistically on the average for large scale But it turns out that…