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Comment on “The Notion of Locality in Relational Quantum Mechanics”

The Original Article was published on 29 January 2019


A recent paper (Martin-Dussaud et al. in Found Phys 49:96, 2019) has given a lucid treatment of Bell’s notion of local causality within the framework of the relational interpretation of quantum mechanics. However, the authors went on to conclude that the quantum violation of Bell’s notion of local causality is no more surprising than a common cause. Here, I argue that this conclusion is unwarranted by the authors’ own analysis. On the contrary, within the framework outlined by the authors, I argue that far from saving the notion of ‘locality’ from the grip of Bell’s theorem, the authors have deprived it of a meaningful definition.

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I thank G. Barreto Lemos for helpful feedback on an earlier draft. This work was supported in part by the John E. Fetzer Memorial Trust.

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Correspondence to Jacques Pienaar.

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Pienaar, J. Comment on “The Notion of Locality in Relational Quantum Mechanics”. Found Phys 49, 1404–1414 (2019).

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