Logical Pre- and Post-Selection Paradoxes are Proofs of Contextuality

  title={Logical Pre- and Post-Selection Paradoxes are Proofs of Contextuality},
  author={Matthew F Pusey and Matthew Leifer},
  journal={arXiv: Quantum Physics},
If a quantum system is prepared and later post-selected in certain states, "paradoxical" predictions for intermediate measurements can be obtained. This is the case both when the intermediate measurement is strong, i.e. a projective measurement with Luders-von Neumann update rule, or with weak measurements where they show up in anomalous weak values. Leifer and Spekkens [quant-ph/0412178] identified a striking class of such paradoxes, known as logical pre- and post-selection paradoxes, and… 
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