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Spin effects

  1. Dec 7, 2009 #1
    I read that you can't directly measurethe direction of spinfor asingleelectron, but you can preforman experiment to see if two electrons are "spinning the same way" or "opposite ways". I know electron spin isn't like normal spinning.

    Let's say we have two pairs of electrons, each pair close together. One pair spins the same way, the other opposite ways. What will each pair of electrons do? How is spin measured this way?
  2. jcsd
  3. Dec 7, 2009 #2


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    You in fact can measure the "direction" of spin for a single electron. That's what the Stern-Gerlach experiment is about. But note that it's only the projection of the spin of the electron onto your axis that you can measure (either +1/2 or -1/2). You can, in fact, never align your axis with the actual direction of spin of the electron, since the electron doesn't have an actual direction of spin.
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