Talk:Interpretations of quantum mechanics

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Comprehensive removal of content[edit]

User:Waleswatcher removed large chunks of text in a revert, saying "reverting to a superior older version. Two "interpretations" are lost (Popper and hydrodynamic). I don't think either is notable/correct enough to be included, but wouldn't strongly object to adding back". I would find it good if such comprehensive changes to the article were discussed on the talk page and at least recorded here so that future editors of this article can easily find it.

--Fixuture (talk) 18:14, 8 June 2016 (UTC)

Probably Ww should answer, but after a quick glance in the diff, I see that at least some of the removed material had the flavor of a now, by the physics community, topic-banned (quantum physics) POV-pushing editor. This can only be an improvement. YohanN7 (talk) 13:57, 9 June 2016 (UTC)
That's exactly right - most of the material I removed was added by that now topic-banned editor, to the substantial detriment of the article. However it's possible removed some valuable material in that revert, so please feel free to add anything back. I suspect those two interpretations are not notable, but they were not the main reason for the revert (else I would have just removed those). Waleswatcher (talk) 14:43, 11 June 2016 (UTC)
As a Theoretical Physicist interested in diverse interpretations of Quantum Mechanics, I would prefer to see more interpretations rather than fewer, regardless of how "notable", or otherwise. DWHalliday (talk) 23:02, 16 October 2016 (UTC)

There is no von Neumann interpretation[edit]

And if there were a von Neumann interpretation, it would not be identical with the consciousness causes collapse interpretation. The name von Neumann interpretation was apparently created on January 2010 on the main article by a single contributor who didn't wrote anything else on wikipedia. The name Wigner was added on 21 February 2010 in an apparent attempt to fix the previous mistake.

None of the references of the article on the consciousness causes collapse interpretation uses the name von Neumann interpretation or von Neumann-Wigner interpretation. The closest is a single use of von Neumann-Wigner quantum theory and multiple uses of von Neumann quantum theory in the article of H. Stapp from 2001. (That information has been reported here.)

Hence I will change the terminology back to the terminology before the mistake, i.e. replace both von Neumann interpretation and von Neumann/Wigner interpretation by the old name consciousness causes collapse. This is independent of whether it makes sense to rename the Von Neumann–Wigner interpretation article. --Jakito (talk) 01:35, 15 February 2017 (UTC)

Unfortunately, I have the feeling the name "the Von Neumann–Wigner interpretation" is around – whereas the name " the consciousness causes collapse interpretation" isn't around as a name for the thing. None of von Neumann or Wigner deserve to have their name dragged in the dirt. Undoubtedly, Wigner later regretted having planted the whole idea. I bet he only took it as a challenge to find a consistent (because it is consistent with experiment) interpretation. But this is not for me or Wikipedia to rectify. YohanN7 (talk) 11:29, 15 February 2017 (UTC)
WP:RSs certainly don't say that Von Neumann originated or supported "consciousness causes collapse". John von Neumann, in his 1932 book The Mathematical Foundations of Quantum Mechanics focused on the chain of causal processes that constitute a "measurement" (now called a "Von Neumann chain").[1], [2] p.526, [3] p.207, For example, in measuring the spin of a photon, the photon mus be detected by a polarizing photodetector, and the signal amplified, displayed, and then observed by the experimenter. If the photon is in a superposition, somewhere in this chain the state of the apparatus changes from a superposition to a single state which is observed by the experimenter. This is "wavefunction collapse". Von Neumann just pointed out that the mathematics allowed the point of "wavefunction collapse" to be considered to occur at any point in this chain between the particle striking the detector and the "subjective perception" of the human observer. He suggested that either the detection or perception point be considered the location of wavefunction collapse, but nowhere expressed a preference.[4] In 1939, F. London and E. Bauer argued that it occurred at perception, originating the "consciousness causes collapse" interpretation.
@YohanN7I: "consciousness causes collapse" most certainly is the WP:COMMONNAME for this interpretation; it is found in hundreds of books. This name also is clearer for general readers, and doesn't raise controversial issues of whether Von Neumann or Wigner supported it, so it should stand. --ChetvornoTALK 16:33, 15 February 2017 (UTC)
I take that as good news. Then there's still the main article on the subject to rename. YohanN7 (talk) 09:11, 16 February 2017 (UTC)
It does seem to me that someone doesn't have to support something, just because it is named after that person. But I suppose there is some suggestion, for those not reading carefully, that the named person supported the idea. Either name is fine with me. Gah4 (talk) 18:16, 1 September 2017 (UTC)

Since the intricacy of a quantum system is exponential[edit]

The article says: Since the intricacy of a quantum system is exponential, but I wonder which variable it is an exponential of. It does seem that QM is difficult for people to understand, but that doesn't make it exponential. It seems to me that classical mechanics, with infinite theoretical precision, is exponentially detailed. Gah4 (talk) 16:10, 25 May 2017 (UTC)

Challenges to Interpretation[edit]

The section Challenges to interpretation is currently a total mess. The usable content (comments on role of the observer, nonlocality, complementarity, size of Hilbert space) is mostly duplicated elsewhere in the article. I blanked the section as WP:JUNK but was reverted; let's try to build a consensus. I don't think much of the current material should remain in mainspace. Porphyro (talk) 15:00, 31 May 2017 (UTC)

The list actually does list some difficulties that any interpretation must address. It could remain (if edited). The following text seems to attempt to illustrate the list items, one by one. If this is duplicated later on, it could either be cut out or shortened and merged into the list. YohanN7 (talk) 10:04, 1 June 2017 (UTC)
I don't object to the concept of such a section, but I think what we have currently is very poor. I personally would not consider that "[l]ack of interest on this subject by Dirac and other notables (including Feynman)" poses a fundamental problem to the interpretation of the theory. Entry (1) is also very vague and to my mind not properly sourced. The explanatory notes are mostly weak too, to my view, containing incoherent rhetorical questions such as "[y]et how do we find in a specific location a particle whose wavefunction of mere probability distribution of existence spans a vast region of space?". It grants features of the MWI interpretation to the interpretation-agnostic concept of decoherence ("Yet quantum decoherence grants that all the possibilities can be real, and that the act of observation/measurement sets up new subsystems.") In the last two paragraphs, we have unwikified and content alongside totally unsourced content. Porphyro (talk) 11:25, 1 June 2017 (UTC)
I think that the section is more confusing than helpful. Roger (talk) 04:33, 2 June 2017 (UTC)
This is not the only confusing feature of this whole article. And I don't say this as a negative criticism: Wikipedia is a work in progress and some doubt and "confusion" should be expected specially in a subject that caused huge confusion among major classical figures. Feynman used to praise the value of "doubt". Talking about Feynman and Dirac: their lack of participation on interpretational matters is not an isolated event. Others followed that route and even today many notable quantum practitioners abstain from participating which does represent a challenge to advance the subject. (talk) 13:28, 3 June 2017 (UTC)
Ha, yes, that's actually a point. Attempting an interpretation is risky business. You'd risk your reputation. Every interpretation has some more or less bizarre features imoFace-smile.svg YohanN7 (talk) 07:26, 5 June 2017 (UTC)

What do you think of the "Principle Based Symbiotic Model of Quantum Physics" by Klaus Fröhlich?[edit]

"Abstract: The symbiotic model of quantum physics considers mathematical, scientific and philosophical principles and makes testable predictions. When measuring no particle develops, but a stable control system. The control system forms from quantum information and the control system acts on quantum information (monism). The necessary information and properties are developed in an evolutionary process of perception and innovation." (talk) 16:01, 14 June 2017 (UTC)

Sentences added as minor edits[edit]

The following unsourced statement was added as a supposedly minor edit to section The Copenhagen interpretation by user Arlene47 on 10 October 2013‎ (and later re-added in an article restoration on 6 May 2016):

  • What collapses in this interpretation is the knowledge of the observer and not an "objective" wavefunction.

Also, the following statement was added to section Many worlds (also unsourced, also minor edit, same user, same date):

  • In this interpretation the wavefunction has objective reality.

Question: Are there any sources that confirm the above two statements? If not, should they be in the article? -- HLachman (talk) 18:07, 1 September 2017 (UTC)

As far as I know, there is no standard for what is, and isn't, a minor edit. Personally, I mostly don't check that box. I am not against removing the statements. Gah4 (talk) 18:51, 1 September 2017 (UTC)