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Reading the value of a qubit without changing its value

  1. Dec 1, 2009 #1
    From the http://physicsworld.com/cws/article/news/23637
    How can that be possible? Isn't that a violation of the No-cloning theorem?
    Last edited by a moderator: Apr 24, 2017
  2. jcsd
  3. Dec 1, 2009 #2
    Their was a phase change in the RF signal that was sent to the Cooper-pair transistor. This phase change corresponds to the ground state and the excited state of the electron that tunneled through the dielectric.
    Because the phase change was observed without actually disturbing the transistor, their knowledge of the state of the tunneled electron is now known, and the no-cloning theorem demands that the state of the tunneled electron be always unknown and arbitrary.
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