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arXiv · 1205.6135

Irreversibility, Information and Randomness in Quantum Measurements

S. N. Mayburov
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Abstract

Irreversibility in quantum measurements is considered from the point of quantum information theory. For that purpose the information transfer between the measured object S and measuring system O is analyzed. It's found that due to the principal constraints of quantum-mechanical origin, the information about the purity of S state isn't transferred to O during the measurement of arbitraryS observable V. Consequently O can't discriminate the pure and mixed S ensembles with the same . As the result, the random outcomes should be detected by O in V measurement for S pure ensemble of V eigenstate superposition. It's shown that the outcome probabilties obey to Born rule. The influence of O decoherence by its environment is studied, however the account of its effects doesn't change these results principally.

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S. N. Mayburov. 2012-05-28. Irreversibility, Information and Randomness in Quantum Measurements. https://arxiv.org/abs/1205.6135

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