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Why does the electron have a magnetic moment?

  1. Apr 12, 2014 #1
    Hi.

    I thought magnetic moment arose from closed loops of charge currents. How does then the angular momentum of the electron produce a magnetic moment? I mean, the electron is not a loop.

    Am I wrong in my initial assumption or am I understanding things too "classically"?

    Thanks.
     
  2. jcsd
  3. Apr 12, 2014 #2

    Meir Achuz

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    You are thinking too classically. The electron's magnetic moment arises from the relativistic QM Dirac equation for the electron.
     
  4. Apr 12, 2014 #3

    dextercioby

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    You don't need Dirac's equation to derive the magnetic moment of the electron. Pauli's nonrelativistic equation will suffice.
     
  5. Apr 12, 2014 #4
    I see. Then saying that the magnetic moment arises from its rotation and its charge is just oversimplifying things, right?
     
  6. Apr 12, 2014 #5

    Meir Achuz

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    Right. Pauli's equation can include the moment, but does not derive it as a necessity.
     
  7. Apr 13, 2014 #6

    dextercioby

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    Pauli's equation always includes the magnetic moment, because it automatically includes the spin.
     
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