Talk:Ensemble interpretation

The article can't decide what it is about.
As currently organized the page mixes up different ideas about "ensemble". As a reader I can't tell what 'it' is.

A clearer approach would view the topic as "ensemble interpretations", plural, and proceed to enumerate, compare, and contrast them. Johnjbarton (talk) 19:02, 22 August 2023 (UTC)


 * Here is a comprehensive review up through 1992:
 * ENSEMBLE INTERPRETATIONS OF QUANTUM MECHANICS. A MODERN PERSPECTIVE D. HOME* and M.A.B. WHITAKER; PHYSICS REPORTS (Review Section of Physics Letters) 21(1, No. 4 (19Y2) 223—317 Johnjbarton (talk) 23:21, 23 August 2023 (UTC)
 * A historical review is The Ensemble Interpretation of Quantum Mechanics and Scientific Realism by Alexander Pechenkin Acta Baltica Historiae et Philosophiae Scientiarum Vol. 9, No. 1 (Spring 2021) DOI : 10.11590/abhps.2021.1.01 Johnjbarton (talk) 15:40, 24 August 2023 (UTC)

"Measurement and collapse"
Ballentine's 1970 paper contains a long section on measurement. He says the measurement problem and collapse (state reduction) are artifacts of non-ensemble interpretation. For example: ''The discussion of the analysis of measurement according to the Statistical Interpretation was so simple and natural that further comment almost seems redundant. ''

The summary in this article seems completely at odds with the paper. Rather than a summary, the section appears to be a length incoherent criticism.

The separate subsection labeled Criticism reference a paper by Mermin which does not reference any specific ensemble papers or interpretations. Mermin simply says he is working on an interpretation which does not rely on ensembles (for reasons that seem puzzling but that is beside the point). Mermin's paper is certainly not a study the in any way refutes Ballentine. Johnjbarton (talk) 23:48, 22 August 2023 (UTC)

"Schrödinger's cat"
The section "Schrödinger's cat" has no references. It starts out with a claim about ensemble interpretation "superpositions are nothing but subensembles", then critiques the very subject it has incorrectly summarized, also without attribution.

Ballentine did address the "Schrödinger's cat" and he does consider it trivial. I'll try to find that reference before deleting this section. Johnjbarton (talk) 00:23, 23 August 2023 (UTC)


 * At least one place that Ballentine discusses the cat is Classicality without Decoherence: A Reply to Schlosshauer Leslie Ballentine, Found Phys (2008) 38: 916–922 DOI 10.1007/s10701-008-9242-0.
 * He dismisses the cat as simply isomorphic to the "measurement problem". The cat is a macroscopic pointer: it is either alive or dead when the observer reads the pointer. Thus is entirely equivalent to a dot on a detector screen appearing to the left or right side. If the cat is mysterious, then measurement is mysterious and vise versa. Johnjbarton (talk) 15:18, 24 August 2023 (UTC)

Original research: Preparative and observing devices as origins of quantum randomness
The section "Preparative and observing devices as origins of quantum randomness" has numerous references in the first and last paragraphs. In between is an essay without attribution.

I don't think the material is all incorrect but some of it reads like extrapolation or wishful thinking. The last paragraph in particular is incorrect about Einstein (he viewed QM as incomplete because it was an ensemble theory) and the vague criticism of Ballentine is unreferenced. Johnjbarton (talk) 15:31, 27 August 2023 (UTC)