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Are they spinning around the nucleus? If so what makes them move? I just do not understand how they move or if they are "attracted" to something is it another particle that makes it move.

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marked as duplicate by joshphysics, David Z Aug 14 '13 at 19:53

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The electron is an elementary particle, bound by the rules of Quantum Mechanics.

It is not a particle like a tiny billiard ball, it is a quantum mechanical entity which sometimes does have mass and a position in spacetime (x,y,z,t) and sometimes it manifests as a probability wave in dimensions commensurate to h, the Planck constant . The boundary conditions of the problem define which will be the manifestation, particle or probability wave, when a measurement is made of a particular electron.

This means that when an electron is free , not in a potential well, measurements will show a track defining a classical trajectory of its motion.

electron photo

Bubble chamber photograph of an electron knocked out of a hydrogen atom

The electron you see knocked off before the knock was in an orbital around the proton nucleus of the hydrogen atom. An orbital, not an orbit, because its location is probable, described by a probability wave given by a mathematical formula, the square of the wavefunction which is a solution of the potential problem "electron and proton in the field of each other".


The shapes of the first five atomic orbitals: 1s, 2s, 2px, 2py, and 2pz. The colors show the wave function phase. These are graphs of ψ(x, y, z) functions which depend on the coordinates of one electron. To see the elongated shape of ψ(x, y, z)2 functions that show probability density more directly, see the graphs of d-orbitals below.

So the electron in its previous life was not orbiting the proton, the way the moon orbits the earth, but it had a probability of being in a particular (x,y,z) when probed.

So in the image, the electron moves because another particle kicked it and transferred momentum enough to free it from the proton of the hydrogen atom. When in a orbital it is in a steady state situation, except its position is undefined within the limits given by the probability derived from the wavefunction, which depends on the potential in the problem.

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From a practical standpoint, based on my perception of the universe, this makes no sense! How can I come to accept this as scientific fact? Please help! –  Ronaldo Nascimento Aug 14 '13 at 19:58
It has taken over 80 years for the scientific community to delve into the microcosm, gather the data and develop the theory that explains it. It used to be that quantum mechanics did not impinge on everyday life, but since the rapid development of electronics, transistors etc our everyday life does depend on the foundation of QM. To accept it you would have to spend time to study physics at more than an elementary level. –  anna v Aug 14 '13 at 20:10
@Ronaldo: It seems experimentation and careful observation tell us that the universe is far far more bizarre than human direct perception, intuition or common sense can comfortably encompass. You probably shouldn't expect GR, QM etc to make sense in terms of simple analogues to human scale mechanics. –  RedGrittyBrick Aug 14 '13 at 23:32
I should add in my comment that quantum mechanics is the foundational level of everything in nature. The macrocosm is built up from the microcosm smoothly. Before the modern era there were not many observations that gave a hint that the classical world could not be extended to the tiny dimensions. Every day intuition would more or less work, but let us not forget that every day intuition gave us aristotelian physics which was wrong on many aspects and kept progress in science back by the dogmatism of the church through the middle ages. –  anna v Aug 15 '13 at 3:32
in this answer physics.stackexchange.com/questions/72927/… to a related question I think I give the good reasons why our classical physics that works so well in the macrocosm cannot be extrapolated to the microcosm but quantum mechanics became necessary as a proposition. –  anna v Aug 15 '13 at 3:36

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