Price, Huw (2026) Retrieving the Baby: Reichenbach’s Principle, Bell Locality, and Selection Bias. [Preprint]

Text SelectionArtefacts.pdf Download (571kB)

Abstract

In his late piece ‘La nouvelle cuisine’ (Bell 1990), John Bell describes the steps from an intuitive, informal principle of locality to a mathematical rule called Factorizability. This rule stipulates that when possible past causes are held fixed, the joint probabilities of outcomes of spacelike separated measurements, conditional on measurement settings, be the product of the local conditional probabilities individually. Bell shows that Factorizability conflicts with predictions of QM, predictions since confirmed in many experiments. However, Bell warns his readers that the steps leading to Factorizability should ‘be viewed with the utmost suspicion’. He says that ‘it is precisely in cleaning up intuitive ideas for mathematics that one is likely to throw the baby out with the bathwater’ (2004, 239). Bell’s suspicions were well-founded, for he himself misses an important baby. Here we retrieve and identify it: it is selection bias. We explain how failure of Factorizability may be regarded as a selection artefact, requiring no violation of locality in the intuitive, conceptual sense with which Bell begins his analysis. The argument begins with a central principle of causal discovery, Reichenbach’s Principle of Common Cause (PCC). It is well known that correlations due to selection bias are not subject to PCC. Several writers have proposed that EPR–Bell correlations are also an exception to PCC, but it has not been noticed that they fall under this well-known exclusion. The point is relevant not only to the status of Bell nonlocality, but also for statistics and causal modeling. For these fields, the news is that selection effects play a ubiquitous role in quantum phenomena, in a form akin to collider bias.

---

Export/Citation:

EndNote | BibTeX | Dublin Core | ASCII/Text Citation (Chicago) | HTML Citation | OpenURL

Social Networking:

Share |

---

Item Type:	Preprint
Creators:	Creators Email ORCID Price, Huw 0000-0002-9091-760X
Keywords:	Bell correlations, selection bias, collider bias, entanglement
Subjects:	General Issues > Causation Specific Sciences > Probability/Statistics Specific Sciences > Physics > Quantum Mechanics
Depositing User:	Prof Huw Price
Date Deposited:	28 Feb 2026 13:35
Last Modified:	28 Feb 2026 13:35
Item ID:	28387
Subjects:	General Issues > Causation Specific Sciences > Probability/Statistics Specific Sciences > Physics > Quantum Mechanics
Date:	19 February 2026
URI:	https://philsci-archive.pitt.edu/id/eprint/28387

Monthly Views for the past 3 years

Monthly Downloads for the past 3 years

Plum Analytics

Actions (login required)

View Item