'Two Dogmas' Redux

Jeffrey Bub

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arXiv · 1907.06240

'Two Dogmas' Redux

Jeffrey Bub

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Abstract

About ten years ago, Itamar Pitowsky and I wrote a paper, 'Two dogmas about quantum mechanics,' in which we outlined an information-theoretic interpretation of quantum mechanics as an alternative to the Everett interpretation. Here I revisit the paper and, following Frauchiger and Renner, I show that the Everett interpretation leads to modal contradictions in 'Wigner's-Friend'-type scenarios that involve 'encapsulated' measurements, where a super-observer (which could be a quantum automaton), with unrestricted ability to measure any arbitrary observable of a complex quantum system, measures the memory of an observer system (also possibly a quantum automaton) after that system measures the spin of a qubit. In this sense, the Everett interpretation is inconsistent.

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Jeffrey Bub. 2019-07-22. 'Two Dogmas' Redux. https://arxiv.org/abs/1907.06240

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