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Manipulating spin of entangled particles

  1. Aug 24, 2013 #1
    Hello all!

    I'm trying to wrap my head around this quantum entanglement thingy. As far as I have understood, if you have two entangled particles, say two electrones, it is impossible to predict their spins since they are thought to be in superposition of both up and down. But if you measure the spin of one of them, the wave function collapses and the other instantly adopts the opposite spin.

    But what happens if you manipulate the spin of one of the electrones, once you know it?

    Let's say you put one of the entangled electrones in a strong magnetic field and change its spin from up to down. Would the other electrone respond to this and change its own spin from down to up the moment you did it?

    I'm new to all this, but really fascinated. I'm sorry if this question has been addressed before. I've been watching youtube-videos, and people seem a bit confused. Some say "whatever you do to one of the particles, the other will do the same", but that's not really true, is it?

    Thanks in advance!
  2. jcsd
  3. Aug 24, 2013 #2


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    Science Advisor

    Nope! The entanglement affects only the initial state of the particles. Once that is resolved, they're free to act independently of each other.
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