A no-summoning theorem in relativistic quantum theory

  title={A no-summoning theorem in relativistic quantum theory},
  author={Adrian Kent},
  journal={Quantum Information Processing},
  • A. Kent
  • Published 24 January 2011
  • Philosophy, Physics
  • Quantum Information Processing
Alice gives Bob an unknown localized physical state at some point P. At some point Q in the causal future of P, Alice will ask Bob for the state back. Bob knows this, but does not know at which point Q until the request is made. Bob can satisfy Alice’s summons, with arbitrarily short delay, for a quantum state in Galilean space-time or a classical state in Minkowski space-time. However, given an unknown quantum state in Minkowski space-time, he cannot generally fulfil her summons. This no… 

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