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Quantum Information, Irreversibility and State Collapse in Some Microscopic Models of Measurement

S. Mayburov
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Abstract

The quantum measurement problem considered for measuring system (MS) model which consist of measured state S (particle), detector D and information processing device O. For spin chains and other O models the state evolution for MS observables measurements studied. It's shown that specific O states structure forbids the measurement of MS interference terms which discriminate pure and mixed S states. It results in the reduction MS Hilbert space to O representation in which MS evolution is irreversible, which in operational formalism corresponds to S state collapse. In radiation decoherence O model Glauber restrictions on QED field observables results in analogous irreversible MS + field evolution. The results interpretation in Quantum Information framework and Rovelli Relational Quantum Mechanics discussed.

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S. Mayburov. 1999-11-24. Quantum Information, Irreversibility and State Collapse in Some Microscopic Models of Measurement. https://arxiv.org/abs/quant-ph/9911105

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