ψ-Epistemic models are exponentially bad at explaining the distinguishability of quantum states.

@article{Leifer2014EpistemicMA,
  title={$\psi$-Epistemic models are exponentially bad at explaining the distinguishability of quantum states.},
  author={Matthew Leifer},
  journal={Physical review letters},
  year={2014},
  volume={112 16},
  pages={
          160404
        }
}
  • M. Leifer
  • Published 30 January 2014
  • Philosophy
  • Physical review letters
The status of the quantum state is perhaps the most controversial issue in the foundations of quantum theory. Is it an epistemic state (state of knowledge) or an ontic state (state of reality)? In realist models of quantum theory, the epistemic view asserts that nonorthogonal quantum states correspond to overlapping probability measures over the true ontic states. This naturally accounts for a large number of otherwise puzzling quantum phenomena. For example, the indistinguishability of… 
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