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Facts are relative

The discussion of the quantum mechanical Wigner’s friend thought experiment has regained intensity. Recent theoretical results and experimental tests restrict the possibility of maintaining an observer-independent notion of measurement outcomes.

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Fig. 1: The extended Wigner’s friend thought experiment.


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Correspondence to Časlav Brukner.

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Brukner, Č. Facts are relative. Nat. Phys. 16, 1172–1174 (2020).

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