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Analysis of the role of von Neumanns projection postulate in the canonical scheme of quantum teleportation and main quantum algorithms

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 Added by Andrei Khrennikov
 Publication date 2008
  fields Physics
and research's language is English




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Modern development of quantum technologies based on quantum information theory stimulated analysis of proposed computational, cryptographic and teleportational schemes from the viewpoint of quantum foundations. It is evident that not all mathematical calculations performed in complex Hilbert space can be directly realized in physical space. Recently by analyzing the original EPR paper we found that they argument was based on the misuse of the von Neumanns projection postulate. Opposite to von Neumann, Einstein, Podolsky and Rosen (EPR) applied this postulate to observables represented by operators with degenerate spectra. It was completely forbidden by von Neumanns axiomatics of QM. It is impossible to repeat the EPR considerations in the von Neumanns framework. In this note we analyze quantum teleportation by taking into account von Neumanns projection postulate. Our analysis shows that so called quantum teleportation is impossible in von Neumanns framework. On the other hand, our analysis implies that the main quantum algorithms are totally consistent with von Neumanns projection postulate.



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