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arXiv · 1301.4328

What is a quantum-mechanical 'weak value' the value of?

Bengt E Y Svensson
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Abstract

A so called 'weak value' of an observable in quantum mechanics (QM) may be obtained in a weak measurement + post-selection procedure on the QM system under study. Applied to number operators, it has been invoked in revisiting some QM paradoxes (e.g., the so called Three Box paradox and Hardy s paradox). This requires the weak value to be interpreted as a bona fide property of the system considered, a par with entities like operator mean values and eigenvalues. I question such an interpretation; it has no support in the basic axioms of quantum mechanics and it leads to unreasonable results in concrete situations.

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Bengt E Y Svensson. 2013-01-18. What is a quantum-mechanical 'weak value' the value of?. https://doi.org/10.1007/s10701-013-9740-6

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