The ‘Wigner’s friend’ thought experiment illustrates the puzzling nature of quantum measurement. Časlav Brukner discusses how recent results suggest that in quantum theory the objectivity of measurement outcomes is relative to observation and observer.
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The author declares no competing interests.
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Brukner, Č. Wigner’s friend and relational objectivity. Nat Rev Phys 4, 628–630 (2022). https://doi.org/10.1038/s42254-022-00505-8
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