Talk:Wheeler's delayed-choice experiment

Retrograde but not "causality"
There seem to be multiple confusions in this article: first, as to what Wheeler actually believes, and secondly, the ideas surrounding retrograde influence, not to be confused with retrograde causality (retrocausality). So for example in the two-state vector formalism (TSVF) there is a backward-time component, but it is not causal. It would seem that the Wheeler experiments are fully consistent with TSVF, but this is not mentioned or discussed here. 67.198.37.16 (talk) 18:47, 18 September 2015 (UTC)

Can this be right?
What is this sentence (from the second paragraph of the introduction supposed to mean?


 * Therefore, it is commonly said that in a double-slit experiment a photon exhibits its wave nature when it passes through both of the slits and appears as a dim wash of illumination across the detection screen, and manifests its particle nature when it passes through only one slit and appears on the screen as a highly localized scintillation.

My understanding is different: Every photon, regardless of whether one slit is open or two are open, exhibits its "particle nature" when it interacts with the screen as a "highly localized scintillation." The entire ensemble of photons exhibits "wave nature" when the sum of all of those highly localized scintillations forms a pattern on the screen---either a "dim wash" when one slit is open, or a "interference pattern" of alternating bands of light and dark when both slits are open.


 * to answer this what you have to understand is that the only way there can be an interference pattern is if the photon interferes with itself. but it cannot both be a particle, and interfere with itself.  Hence the photon must have decided right before the slit at the latest whether or not to be a wave or a particle. does that help?  — Preceding unsigned comment added by 64.89.215.156 (talk) 22:44, 2 March 2019 (UTC)

There can be neither "dim wash" nor interference pattern if there is only ever one photon. A single photon interacts at exactly one point. The interesting thing about single photon experiments is that photons are emitted one at a time so that only one could possibly be in transit through the apparatus a time and yet an interference pattern eventually develops. However, it develops one point at a time. John G Hasler (talk) 01:33, 17 February 2020 (UTC)


 * Agree with John G Hasler and the IP. The whole introduction needs to be rewritten.  It says correctly the photon is only ever 'detected' at a single place and time by absorption.  But the interference pattern is observed by repeating the experiment, in the probability of detection of the successive photons at different points.  Although the luminosity can be reduced until on average one photon passes through the apparatus at a time, proving that a single photon can 'interfere with itself', an interference pattern cannot be created by a single photon, it appears in the random detected locations of multiple photons that have passed through the same apparatus.


 * But the introduction does not describe what the Wheeler experiment is, or what this long infodump has to do with it.--ChetvornoTALK 20:38, 10 May 2021 (UTC)

I could not stand the "dim wash" so I rewrote the introduction. It is clearly wrong, even just by reading the double-slit experiment page. Dragomang87 (talk) 10:39, 22 June 2021 (UTC)

Where do the Wheeler quotes come from? Books, papers, interviews, lectures?
The article doesn't say. Same thing looking up wheeler quotes on the famous person quotation websites. They quote people but don't say where the quotes came from. It's so frustrating! I need to know for something important I'm writing. 2600:8801:BE31:D300:A8FF:7572:5B76:92C8 (talk) 00:24, 5 July 2022 (UTC)

"experimenters generally say"
I removed an unreferenced (and unverifiable) claim that "experimenters generally say".

The entire point of the subject of this article is comparisons of hypothesis, not polls of personal opinions. Johnjbarton (talk) 14:46, 18 June 2023 (UTC)