Talk:Uncertainty principle

Observer Effect

Is the quoted statement correct? Didn't the modern double-slit experiment, conducted sometime after the sited reference, reveal that it was not simply detecting the particle that collapsed the wave function but rather the observation of the result? Please help!

"It must be emphasized that measurement does not mean only a process in which a physicist-observer takes part, but rather any interaction between classical and quantum objects regardless of any observer." — Preceding unsigned comment added by 2a02:c7d:784d:5500:2c4b:22cc:fce5:28c0 (talk)

The ideal of the detached observer -iatrogenic Building Blocks

Hello there. In the section entitled 'The ideal of the detached observer', though Pauli mentions that he disagrees with Einstein's refutation of the uncertainty principle with respect to the observer influencing the thing observed, adding that he hopes his memory accurately reported their conversation, we do not hear Pauli's corrective to Einstein's attempt to refute the idea of something changing while/upon being observed. I'm sure his recall was perfectly good and it probably doesn't matter as the example cited, the position of the moon being unchanged whether we observe it or not (a bit like Bishop Berkeley's kitchen vanishing once he moves into the living room) is exactly (with all due respect to Einstein) the wrong scenario with which to test the hypothesis. A simpler scenario whereby an inspector is observing a junior teacher teach captures the theory a little more firmly. The inspector's presence distorts the lesson being given though s/he perhaps is unaware to what extent his presence changes the thing that he is observing. Descartes x/y axis assumes a new dimension Z, 'the catalytic observer' or perhaps better 'the subjective correlative' (to finesse T.S. Eliot), it seems to me (though I know nothing about physics). Another scenario might see an art gallery visitor standing before a classical painting and then an abstract painting, the former demanding no participation to consummate its meaning, the latter requiring some. (Unwelcome to settled tastes, the idea of the public participating in art is anti-elitist but nonetheless considered a necessary corrective to self serving elites.) Likewise, developments like Le Nouveau Roman require readers to augment their missing chapters to complete them, thereby assigning or allowing a role for the reader/observer (as Detective fiction does). These simple examples are part of an index of much heavier (complex) applications with respect to the manner in which our judgement is or becomes skewed in certain situations where we passively participate in let's say condemning lust while living a life of unwelcome and enforced celibacy. Our often failure to see that our own pathology (sorry) influences our view of the thing observed can get us into all kinds of trouble. Psychoanalysts have something called the object oriented question which is 'employed' on particularly resistant/ repressed individuals who will only surrender an image of their ego unwillingly and so such people speak through objects (as we all invariably do) to express themselves, so enabling the therapist to get an idea of their psychic composition. The therapist him or herself may possess all kinds of blocks to observing the patient in a clear light. These iatrogenic blocks provide a term which may help differentiate between Einstein's Moon and more subtle examples where the presence of the observer does impact the thing observed. So, I think this section needs a little finessing to either include Pauli's refutation or a better example might be found to expound the actual beneficial application whereby a scenario is altered by virtue of being a participant. I hope I haven't confused matters. Thank you. M.H. p.s. If you doubt the role of the observer, consider the oft told story of King Faisal waking disguised in the market to find out what his people were thinking, and saying. He knew that if he showed up as himself, he'd get a very different reception. 'The Deferential Equation', maybe. — Preceding unsigned comment added by 37.125.41.223 (talk)

Popper's criticism section

The last phrase of this section says "this experiment was influenced the formulation of the EPR paradox". Either "was" should be removed or "by" added before "the". Which? Jafaucett (talk) 23:25, 8 May 2024 (UTC)

Thanks I fixed it up, please review. Johnjbarton (talk) 02:36, 9 May 2024 (UTC)

Primary refs in Quantum entropic uncertainty principle

The section "Quantum entropic uncertainty principle" has many primary refs, but this review should be used instead of or in addition:

• Coles, P. J., Berta, M., Tomamichel, M., & Wehner, S. (2017). Entropic uncertainty relations and their applications. Reviews of Modern Physics, 89(1), 015002.

Johnjbarton (talk) 23:05, 13 October 2024 (UTC)

Order of contents

I think the qualitative sections on different relations should be grouped together and the math section moved below that. The section "Critical reactions" is evidently part of History and should set underneath. I notice that @Roffaduft has been rearranging so I will leave this as a suggestion rather than edit now. Johnjbarton (talk) 16:14, 3 November 2024 (UTC)

As the article is a bit of a hodgepodge, I've condensed the material a bit and attempted to place the subsections in chronological order. That is:

1. Start with the quantum mechanical description
2. Next, the general mathematical formalism (which is still pretty quantum mechanical as opposed to "truely" mathematical)
3. Then "generalizations", "equivalent statements" (with a more controversial history), "extensions" etc.

The reason I placed "Harmonic analysis" (i.e. Fourier analysis) a bit higher was to emphasize that the mathematical origins (involving e.g. Cauchy–Schwarz inequality and Chebyshev's inequality) underlying the uncertainty principle actually predate the QM description (although that doesn't become very clear in said subsection).

Regardless, the main issue I have with the article is that it's borderline WP:NOTTEXTBOOK. The subsubsections of "Position-Momentum" are a great example of that.

Kind regards, Roffaduft (talk) 08:08, 4 November 2024 (UTC)

yes surely the qualitative QM description is the most notable and should come early. Maybe an early section devote just to that would make sense.

Maybe add material on the mathematical origins into History before Heisenberg is discussed. I think that would bring out your point more clearly. I wish a few paragraphs of History were earlier but the Heisenberg microscope and the Critical reactions section should be combined and then the section is long. It seems to have a fair number of refs so reduction would not be a priority.

I agree about Position-Momentum. "Proof of the Kennard inequality using wave mechanics" could move under Mathematical or frankly just be deleted as unsourced and undue. Most of the rest of that section is unsourced.

I think most readers would appreciate the different types of uncertainty relations (x-p, E-t, etc) group together. Johnjbarton (talk) 16:55, 4 November 2024 (UTC)