arXiv subjects

G. Bacciagaluppi

Publications and source records attributed to G. Bacciagaluppi.

2 recordsLinked to original sources

arXiv2026

Extending Bell's Theorem: Nonlocality via Measurement Dependence

Besides well-known conditions of locality or factorisability, deriving the Bell inequalities requires assuming that the distribution of hidden variables and Alice's and Bob's measurement settings be independent of each other. We show that (analogously to violations of locality due to action at a distance) certain violations of this Measurement Independence assumption can be associated with a notion of signalling in principle, thus making them also testable in principle, and spell out the appropriate conditions. Accordingly, we show that by imposing no-signalling one can prove a version of Bell's theorem that does not require the assumption of Measurement Independence. We discuss the "Schulman model" as an example, as well as lessons for "experimental metaphysics".

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arXiv2021

Bell Inequality Violation and Relativity of Pre- and Postselection

The Bell inequalities can be violated by postselecting on the results of a measurement of the Bell states. If information about the original state preparation is available, we point out how the violation can be reproduced classically by postselecting on the basis of this information. We thus propose a variant of existing experiments that rules out such alternative explanations, by having the preparation and the postselection at spacelike separation. Unlike the timelike case where one can sharply distinguish Bell inequality violations based on pre- or postselection of a Bell state, in our scenario the distinction between these physical effects becomes foliation-dependent. We call this 'relativity of pre- and postselection'.

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