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تسجيل مستخدم جديدComplementarity has empirically relevant consequences for the definition of quantum states
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Bradley A. Foreman
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The Copenhagen interpretation of quantum mechanics, which first took shape in Bohrs landmark 1928 paper on complementarity, remains an enigma. Although many physicists are skeptical about the necessity of Bohrs philosophical conclusions, his pragmatic message about the importance of the whole experimental arrangement is widely accepted. It is, however, generally also agreed that the Copenhagen interpretation has no direct consequences for the mathematical structure of quantum mechanics. Here I show that the application of Bohrs main concepts of complementarity to the subsystems of a closed system requires a change in the definition of the quantum state. The appropriate definition is as an equivalence class similar to that used by von Neumann to describe macroscopic subsystems. He showed that such equivalence classes are necessary in order to maximize information entropy and achieve agreement with experimental entropy. However, the significance of these results for the quantum theory of measurement has been overlooked. Current formulations of measurement theory are therefore manifestly in conflict with experiment. This conflict is resolved by the definition of the quantum state proposed here.
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Ninety years ago in 1927, at an international congress in Como, Italy, Niels Bohr gave an address which is recognized as the first instance in which the term complementarity, as a physical concept, was spoken publicly [1], revealing Bohrs own thinkin
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We derive complementarity relations for arbitrary quantum states of multiparty systems, of arbitrary number of parties and dimensions, between the purity of a part of the system and several correlation quantities, including entanglement and other qua
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One of the milestones of quantum mechanics is Bohrs complementarity principle. It states that a single quantum can exhibit a particle-like emph{or} a wave-like behaviour, but never both at the same time. These are mutually exclusive and complementary
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