Foundations of Physics

, Volume 48, Issue 11, pp 1568–1589 | Cite as

Quantum Theory and the Limits of Objectivity

  • Richard HealeyEmail author


Three recent arguments seek to show that the universal applicability of unitary quantum theory is inconsistent with the assumption that a well-conducted measurement always has a definite physical outcome. In this paper I restate and analyze these arguments. The import of the first two is diminished by their dependence on assumptions about the outcomes of counterfactual measurements. But the third argument establishes its intended conclusion. Even if every well-conducted quantum measurement we ever make will have a definite physical outcome, this argument should make us reconsider the objectivity of that outcome.


Quantum theory Objectivity Wigner’s friend Brukner Frauchiger and Renner 



Thanks to Jeff Bub for a helpful correspondence on Frauchiger and Renner’s argument, to Časlav Brukner for conversations and correspondence over several years, and to a reviewer for good strategic advice. None of them should be taken to endorse the analysis or conclusions of this paper.


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© Springer Science+Business Media, LLC, part of Springer Nature 2018

Authors and Affiliations

  1. 1.University of ArizonaTucsonUSA

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