Paradoxes , Measurement - Disturbance and Contextuality
نویسنده
چکیده
Many seemingly paradoxical effects are known in the predictions for outcomes of measurements made on preand post-selected quantum systems. A class of such effects, which we call “logical preand post-selection paradoxes”, bear a striking resemblance to proofs of the Bell-Kochen-Specker theorem, which suggests that they demonstrate the contextuality of quantum mechanics. Despite the apparent similarity, we show that such effects can occur in noncontextual hidden variable theories, provided measurements are allowed to disturb the values of the hidden variables.
منابع مشابه
Logical pre- and post-selection paradoxes are proofs of contextuality
If a quantum system is prepared and later post-selected in certain states, “paradoxical” predictions for intermediate measurements can be obtained. This is the case both when the intermediate measurement is strong, i.e. a projective measurements with Lüders-von Neumann update rule, or with weak measurements where they show up in anomalous weak values. Leifer and Spekkens [Phys. Rev. Lett. 95, 2...
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Many seemingly paradoxical effects are known in the predictions for outcomes of measurements made on preand post-selected quantum systems. A class of such effects, which we call “logical preand post-selection paradoxes”, bear a striking resemblance to proofs of the Bell-Kochen-Specker theorem, which suggests that they demonstrate the contextuality of quantum mechanics. Despite the apparent simi...
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Many seemingly paradoxical effects are known in the predictions for outcomes of intermediate measurements made on pre- and post-selected quantum systems. Despite appearances, these effects do not demonstrate the impossibility of a noncontextual hidden variable theory, since an explanation in terms of measurement disturbance is possible. Nonetheless, we show that for every paradoxical effect whe...
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