Talk:Measurement

Quantum measurement

I know that quantum measurement is contentious so I want to say a bit more about my edits of this section.

I removed sentence: Before a measurement is made, a quantum system is simultaneously described by all values in a range of possible values,

This is not correct as can be seen by reading the rest of the paragraph. Measuring a quantum state puts the system in a new state corresponding to the value measured. So obviously then it is obviously not in a state with "all values".

I replaced it with some content derived from and referenced to A. Messiah's book, that addresses the same concept in a more correct way.

I also moved the last sentence up and connected it to the one on "collapse". Penrose, cited in the article talks about both sentences so now the missing citation tag is not needed. Johnjbarton (talk) 15:31, 17 June 2023 (UTC)

Wiki Education assignment: 4A Wikipedia Assignment

This article was the subject of a Wiki Education Foundation–supported course assignment, between 12 February 2024 and 14 June 2024. Further details are available on the course page. Student editor(s): Not Fidel (article contribs). Peer reviewers: Adolfo2213.

— Assignment last updated by Ahlluhn (talk) 00:57, 31 May 2024 (UTC)

Exactness

I was surprised at the use of the word "exactness". I had to look it up. I think the common way this is expressed is "precision". Johnjbarton (talk) 23:31, 14 September 2025 (UTC)

Updating the lead

I propose revising the lead and methodology using the International Vocabulary of Metrology (VIM) that can be found here: https://www.bipm.org/documents/20126/115700832/VIM4_2CD_clean/c6d0dfb2-ddbf-059e-1f74-9b025c9c59d8 , particularly the distinction between measurement error and measurement uncertainty. IndrasBet (talk) 18:03, 20 August 2026 (UTC)