Abstract
AbstractThe notorious Wigner’s friend thought experiment (and modifications thereof) has received renewed interest especially due to new arguments that force us to question some of the fundamental assumptions of quantum theory. In this paper, we formulate a no-go theorem for the persistent reality of Wigner’s friend’s perception, which allows us to conclude that the perceptions that the friend has of her own measurement outcomes at different times cannot “share the same reality”, if seemingly natural quantum mechanical assumptions are met. More formally, this means that, in a Wigner’s friend scenario, there is no joint probability distribution for the friend’s perceived measurement outcomes at two different times, that depends linearly on the initial state of the measured system and whose marginals reproduce the predictions of unitary quantum theory. This theorem entails that one must either (1) propose a nonlinear modification of the Born rule for two-time predictions, (2) sometimes prohibit the use of present information to predict the future—thereby reducing the predictive power of quantum theory—or (3) deny that unitary quantum mechanics makes valid single-time predictions for all observers. We briefly discuss which of the theorem’s assumptions are more likely to be dropped within various popular interpretations of quantum mechanics.
Funder
John Templeton Foundation
Publisher
Springer Science and Business Media LLC
Subject
General Physics and Astronomy
Reference38 articles.
1. Wigner, E. P. Remarks on the Mind-Body Question, 247–260 (Springer, 1995).
2. Deutsch, D. Quantum theory as a universal physical theory. Int. J. Theoret. Phys. 24, 1–41 (1985).
3. Brukner, Č. in Quantum [Un]Speakables II: Half a Century of Bell’s Theorem (eds Bertlmann, R. & Zeilinger, A.) 95–117 (International Publishing, Springer 2017).
4. Brukner, Č. A no-go theorem for observer-independent facts. Entropy 20, 350 (2018).
5. Relaño, A. Decoherence allows quantum theory to describe the use of itself. Preprint at http://arxiv.org/abs/1810.07065 (2018).
Cited by
14 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献