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Do electrons actually spin?

  1. Apr 6, 2012 #1
    I'm reading about properties of electrons in atoms, and it says an electron's position in an atom can be described by energy level, shape, orientation, and spin
    roughly speaking:
    the energy level (n) dictates the radius from the nucleus (probability wise)
    the shape (l) dictates... the shape of the orbital
    the magnetic moment (m_l) dictates the way that shape is oriented (relative to what set of coordinates? I mean "down" isn't towards the center of the earth, I imagine)
    and spin, which dictates... what the electron does when passed through a magnetic field?
    a charge that spins generates a magnetic field?
    the the electron actually rotating about a center axis?

  2. jcsd
  3. Apr 12, 2012 #2
    bump. anything?
  4. Apr 12, 2012 #3


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    Electrons appear to possess angular momentum. Whether or not that means that they actually 'spin' is not particularly relevant or meaningful. They interact with other things as if they do spin.

    Although, to respond to the detail in your OP about what is 'up' or 'down'. The spinning of the electron seems to depend upon its environment so I guess you could say that it is only 'spinning' when it is actually in an atom and an axis can be defined. That's when the +/-1/2 quantum numbers come in to describe the spin. A free electron may behave differently and I'm not sure whether they can be sorted into + and - spin piles. After all, up/down/left/right are not fundamental to an electron that's just hanging there.
    Last edited: Apr 12, 2012
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