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arXiv · 2102.08709

Extended Wigner's friend problem and the internal consistency of standard quantum mechanics

D. Sokolovski·A. Matzkin
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Abstract

The extended Wigner's friend problem deals with two Observers each measuring a sealed laboratory in which a friend is making a quantum measurement. We investigate this problem by relying on the basic rules of quantum mechanics as exposed by Feynman in the well-known "Feynman Lectures on Physics". Although recent discussions have suggested that the extended Wigner's friend problem cannot consistently be described by quantum theory, we show here that a straightforward application of these standard rules results in a non-ambiguous and consistent account of the measurement outcomes for all agents involved.

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D. Sokolovski, A. Matzkin. 2021-02-17. Extended Wigner's friend problem and the internal consistency of standard quantum mechanics. https://doi.org/10.3390/e23091186

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