Evidence for the epistemic view of quantum states: A toy theory

  title={Evidence for the epistemic view of quantum states: A toy theory},
  author={Robert W. Spekkens},
  journal={Physical Review A},
  • R. Spekkens
  • Published 9 January 2004
  • Physics
  • Physical Review A
We present a toy theory that is based on a simple principle: the number of questions about the physical state of a system that are answered must always be equal to the number that are unanswered in a state of maximal knowledge. Many quantum phenomena are found to have analogues within this toy theory. These include the noncommutativity of measurements, interference, the multiplicity of convex decompositions of a mixed state, the impossibility of discriminating nonorthogonal states, the… 
ψ-Epistemic models are exponentially bad at explaining the distinguishability of quantum states.
  • M. Leifer
  • Philosophy
    Physical review letters
  • 2014
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