Talk:Wave–particle duality/Archive 1

message: In texts that talk about detecting light by means of either a "particle detector" or a "wave detector" no information is given as to the suitability of these objects to the tasks to which they are put. Why is the "particle detector" believed to be detecting a particle and not high tide. Conversely why is the "wave detector" detecting a wave-type light and not just showing its own distortion from being collided with a particle-like light.
Furthermore, no explanation is given as for how they know one and only one photon is emitted. 
User:hackwrenchRobert Claypool
:Wave detectors are instruments such as interferometers which rely on wave specific attributes such as diffraction and interference. Particle detectors are instruments such as photodetectors which rely on particle-specific attributes such as momentum and energy. -- Derek Ross |  Talk 23:36, 12 October 2005 (UTC)
thread_title: Flaws

message: Hello,
I (Cdang) made a popularized explaination that was removed by Afshar the 28 Jan 2005 at 15:28 with the comment: Removed oversimplistic and inaccurate "popularized" section.
Of course, I do not support this deletion.
First of all, the text itself:
----
----
To spare room, I put the last version before removal(i.e. 21:54, 14 Mar 2005) instead of the original version and not besides, which should imho not alter the unterstanding of the discussion — Cdang|write me 09:29, 25 Mar 2005 (UTC)
thread_title:  Request for comments: popularized part 

message: From the discussion above, I think that the opposition comes from a misunderstanding. The popularised part is an analogy (the choice of the word "metaphor" in the section title is not neutral); it makes a comparison on only some aspects of the behaviour, not all.
To make things clearer, and to discuss on facts, not on feelings, I propose below a kind of quiz. Everybody is invited to answer it:
* edit the section and copy the table;
* every time you meet a  just remove the  and let your answer to the statement
* please sign your quiz by putting four tilde ~~~~
Cdang|write me 09:12, 23 Feb 2005 (UTC)
thread_title:  Assessment quiz 

message: (William M. Connolley 15:57, 5 Mar 2005 (UTC)
thread_title:  My edits 

message: The whirlpool analogy seems useful to me to aide in visualization.  If the physicists here object to it's inclusion in this article, I suggest you include it in a new article, such as visualization of wave-particle duality and add links from/to this article.  I have found there is an impenetrable divide between those who write for the masses and those who write just for post-grads.  The first group likes to include simple, if not rigorously correct, models, like a globe to represent the Earth.  The post-grads are aghast at such an approximation, as the globe is a hollow paper sphere with a metal rod as an axis, and the Earth is not.  They prefer higly complex theory, impossible to visualize, and understandable only to themselves.  Since there are far more non-post grads than post-grads, you would think they would have the majority in any vote, but, since they spend much less time here than the PhDs, the reverse is the case.  Keeping the two groups away from each other's throats by giving them each their own article may be the only way to "compromise". StuRat 12:45, 8 October 2005 (UTC)
thread_title: I applaud the whirlpool simplification/visualization effort

message: A new section was added by Arnero which was originally named "Intro".  I renamed it to "Theory" and performed a LOT of cleanup in spelling, wording, punctuation, and format.  While this editor appears to have good info to contribute, they don't seem to do a very good job at proofreading their own work.  I would also like an expert in the field to review it for technical accuracy, particularly suspect is the following statement:
:If Psi(x,t) is a state with the lowest Eigenvalue, one says: The pendulum contains zero phonons.
:If Psi(x,t) is a state with the next higher Eigenvalue, one says: The pendulum contains zero phonons.
If they do both mean zero phonons, then the case of more than zero phonons needs to be described. StuRat 15:11, 8 October 2005 (UTC)
replies: text: I took the bold action of just removing the whole section. I found it clear as mud, and felt it contributed nothing to the article. If someone wants to talk about phonons, they should say something like The phonon is another example of wave-particle duality, see phonon for an elementary explanation of what a phonon is. linas 22:27, 8 October 2005 (UTC)

text: Phonons are not even mentioned in Quantum Mechanics courses I'm familiar with.  They appear in solid state physics courses instead. So I can't imagine why they'd be the first example. -- SCZenz 16:57, 9 October 2005 (UTC)

text: I thought your section looked useful, after the wording was cleaned up (by me), but I'm not qualified to talk about the technical value.  It might be a good idea to include it here and let people other than linas comment on whether it's worthy of inclusion. StuRat 15:28, 9 October 2005 (UTC)
thread_title:  New "Theory" section 

message: ->Please comment on inclusion of the above "Theory" section here:
*Support inclusion, provided the phonon error is corrected. StuRat 15:30, 9 October 2005 (UTC)
replies: text: It's also clear to me that you aren't in that category, as you were unable to find the specific flaw in my section (the field vs medium flaw), despite repeated questioning.  However, there is no need to have any technical expertise at all to attempt to build a consensus, using polling as one such method.  Frequently somebody not involved in the discussion can be a better moderator than someone rigidly on one side or the other.  I didn't write the material in question (although I did clean it up), and I'm just fine with it being included or excluded, whichever the consensus is.  User:Arnero did apparently spend a fair amount of time writing this material, however, so to simply remove it without any discussion seems quite rude to me. StuRat 18:34, 9 October 2005 (UTC)
replies: text: From my reading, the two of you somewhat misunderstood each other in the initial discussion.  William did have a legitimate point, that it's quite unnecesary to use wave-particle duality to explain light propogation in empty space, but he stated it quite briefly.  It's not useful to label each other as not understanding the content of the article, either.  As for removing content, it is pretty standard to be bold and remove stuff you know isn't right, as long as you explain it.  If it's disputed, obviously we need to build consensus--I prefer discussion to voting, but the same consensus is going to come out either way in this case. -- SCZenz 19:08, 9 October 2005 (UTC)
replies: text: I agree, except that I think voting is quicker, it gets everyone's opinions listed right up front, instead of trying to read thru pages of dialogue to try to extract each person's opinion. I'm all for settling issues as quickly as possible and moving on, rather than engaging in endless debate, or even worse, edit wars. StuRat 19:47, 9 October 2005 (UTC)

text: As for removing things which are incorrect, I agree there, too, but don't feel the "Theory" section falls into that category.  As near as I can tell, it's not wrong, just perhaps not the best way of explaining wave-particle duality.  In this case, whether it is useful is opinion, and I believe that building a consensus is valuable in such cases. StuRat 19:53, 9 October 2005 (UTC)

text: I rather like the double-slit discussion, although it certainly isn't introductory level material.  I especially like how it leads from wave-particle duality into a discussion of the many worlds theory. Schrodinger's cat is always a fun way to discuss "collapsing the probability function", but again, is not introductory level material.  Since both of those sections are down in the depths of the article, not at the top, I'm just fine with having them here.  Similarly, I'm fine with Arnero's material, as long as it's not near the top. StuRat 21:27, 9 October 2005 (UTC)
thread_title:  Inclusion of "Theory" section ? 

message: I see a lot of confusion about "wave-particle duality".
At one time, it was confusing to everyone. Each of the theories of light ("light is particles" vs. "light is waves") made predictions that matched reality sometimes, but were incorrect other times.
However, physicists have finally figured out a single theory of light that makes predictions that match reality in all experiments.
(Forgive me for giving this Appeal to authority, rather than actually explaining quantum electrodynamics:)
:It is very important to know that light behaves like particles, especially for those of you who have gone to school, where you were probably told something about light behaving like waves. I'm telling you the way it does behave -- like particles. ... waves can combine or cancel out, and the calculations based on this model matched the results of Newton's experiments, as well as those done for hundreds of years afterwards. But when instruments were developed that were sensitive enough to detect a single photon, the wave theory predicted that the "clicks" of the photomultiplier would get softer and softer, whereas they stayed at full strength -- they just occurred less and less often. No reasonable model could explain this fact. So there was a period for a while in which you had to be clever: You had to know which experiment you were analyzing in order to tell if light was waves or particles. This state of confusion was called the "wave-particle duality" of light, ... It is the purpose of these lectures to tell you how this puzzle was finally "resolved". -- Richard Feynman, in QED (book) (1985).
Would this quote (perhaps trimmed down a bit) be something good to stick in the article?
Does this mean that "wave-particle duality" is now merely a historical footnote, like Phlogiston theory?
Or is it still a useful idea, even if we now know it is not exactly true in all cases, like Newtonian physics?
--DavidCary 21:47, 30 November 2005 (UTC)
replies: text: In Quantum Field Theory, which is the general modern theory of particle physics, a photon is treated as a particle just like any other (except for having a different mass, spin, etc. than others, of course).  However, all particles are subject to wave-particle duality.  -- SCZenz 22:34, 30 November 2005 (UTC)
replies: text: All particles are waves. Feynmann probably says that a few paragraphs over. linas 00:31, 1 December 2005 (UTC)
thread_title:  light is particles 

message: This may not belong in the article, but I just wanted to mention for the record that the whole issue basically goes away in modern quantum mechanics. The wave model was particular to early quantum mechanics. This is sometimes called "Wave Mechanics" today, to distinguish it from modern QM. Typically, undergraduate courses in quantum mechanics never get beyond this. Modern QM deals with states of quantum systems as abstract objects—points in Hilbert space, a complex vector space. These can be manipulated with various kinds of mathematical operators, some of which correspond to physical measurements that can be performed on the system. Like an ordinary 3D vector, the states can be expanded in terms of a set of basis vectors. One can extract the "wavefunction" corresponding to a particular state by expanding it in terms of the basis set of position vectors if you like, but you don't have to do this in general.
None of that probably belongs in this article, but my point is that in modern QM an object is neither a wave nor a particle. It is what it is. If you choose to describe the system in a position-space representation you can describe it as having wave-like properties. You're perfectly free to choose another basis set, however, in which case the description may be quite different even though the results are the same. There are an infinite (IIRC) number of basis sets to choose from, so there is nothing particularly special about "waves" or "particles", except that they are kindof intuitive.--Srleffler 01:57, 13 December 2005 (UTC)
thread_title: For the record

message: I complied with your "Good Article" request, but it would be great if this article had a picture. I'm not sure what you could add a picture of, but it looks like this needs one. joturner 17:35, 25 December 2005 (UTC)
thread_title: Picture

message: I have updated the section "Treatment in modern quantum mechanics" to reflect the common understaning of field theory put forth by Weinberg. There were several comments stating that it needed clarification. I hope that this is considered the best approach at explaining it. Please do not remove any of the added content unless you have read "The quantum theory of fields" by Weinberg. That said you are welcome to expand or edit what I have done.
~Dr. Edmonds  — Preceding unsigned comment added by 174.4.58.66 (talk) 08:50, 2 February 2012 (UTC)
thread_title: Update of Treatment in modern quantum mechanics

message: Ref. #6 ( http://www.hep.princeton.edu/~mcdonald/examples/QM/thorn_ajp_72_1210_04.pdf ) is not accessible (AJP paper). Changed the reference to point to the article on the journal's website.
Do it faster Mr Ishizaka (talk) 16:57, 18 July 2018 (UTC)
thread_title: Reference issue

message: Hi there,
I am not a native speaker, but the all section about black body and Planck's theory is composed of uselessly long sentences.
Let's take this one: "By demanding that high-frequency light must be emitted by an oscillator of equal frequency, and further requiring that this oscillator occupy higher energy than one of a lesser frequency, Planck avoided any catastrophe, giving an equal partition to high-frequency oscillators produced successively fewer oscillators and less emitted light."
I do not even understand the end of it: "[...] Planck avoided any catastrophe, giving an equal partition to high-frequency oscillators produced successively fewer oscillators and less emitted light."
Aren't a couple of mistakes here and there?
oscillators? oscillations?
giving? given?
or a coma somewhere maybe?
Globally most sentences in the whole section could be cut in half and still convey an equivalent meaning. Keuj6 (talk) 14:03, 10 February 2019 (UTC)
thread_title:  Shorten sentences in the black body radiation section? 

message: In this section, I propose the deletion of the quote from "L.E. Ballentine, Quantum Mechanics." It is quite long and from a very dated textbook. The lead-in sentence suggests that duality is not a mystery, but the long quote simply says the wave pattern is statistical and the particles don't obey classical rules which we knew anyway. The quote tells us nothing... CometKeeper (talk) 22:56, 23 April 2021 (UTC)
thread_title:  Both particle and wave view 

message: An anonymous contributor introduced above (see Archive 1) the idea that motor traffic, especially at night when only the rear lights are visible, can show particles behaving like waves when the stream of traffic splits to avoid an obstruction. 
Everyday experience on fast main roads includes the phenomenon of heavy traffic repeatedly slowing down, sometimes to a standstill, and bunching up, before moving off to spread out again. This is explained by Boris Kerner's three-phase theory of traffic flow, in which a "wide moving jam" entails a "congestion shock wave" which propagates backwards at what turns out to be around 20 kilometres per hour, whatever the forward speed of the main traffic flow may be.
The wave-form is not easily seen from within the stream, but can be seen from the side when traffic has to form a queue to leave the carriageway. Cars in the inside lane can be seen slowing down, possibly even stopping, while those ahead speed up and separate, leaving enough room for faster traffic in the adjacent lane to cut in. There may be several such segments. To the onlooker this looks like a sound wave, the direction of oscillation being the same as that of propagation.
I have not seen this happen when happen when humans or animals, or even people on horseback, walk or run in the same direction: it seems to be specific to vehicles controlled by humans, rather than a property of the road layout. Perhaps the next generation will discover whether self-driving cars behave this way. Whatever the basis, this seems to me the most visible example of particles behaving like waves. NRPanikker (talk) 17:39, 15 February 2019 (UTC)
replies: text: The archived introduction was probably also off-topic per wp:talk page guidelines. - DVdm (talk) 19:08, 15 February 2019 (UTC)
replies: text: It's only off-topic if we have to confine ourselves to mathematical models of imaginary objects. But the point of these models is to explain real events in terms of things we can imagine. The archived account helped by offering an analogy with something we can actually see. Waves and particles were originally brought in as metaphors to explain things that we can't see. NRPanikker (talk) 01:44, 16 February 2019 (UTC)
replies: text:  But it is off-topic because we must discuss changes to the article here. We cannot discuss the subject or aspects thereoff. See wp:TPG. - DVdm (talk) 12:57, 16 February 2019 (UTC)
replies: text: One point of talk pages is to discuss matters that might be worth putting in the article. It would be pointless to refuse to consider things because they aren't already in it. NRPanikker (talk) 11:43, 17 February 2019 (UTC)
replies: text:  Right. Can you bring a reliable source (as in WP:RS and WP:DUE) that would support the content —and its documented relevance— to be put in the article? With such a source we can discuss. Otherwise it remains off-topic. - DVdm (talk) 12:42, 17 February 2019 (UTC)

text: I don't see any reference to the subjects of quantum mechanics or wave-partucle duality in the Traffic wave and Boris Kerner articles, nor do I find any link between the subjects and Boris Kerner in a Google Books Search or in Google Scholar Search. Perhaps this is some kind of wp:original research of your part? In that case we obviously cannot discuss it here. - DVdm (talk) 18:38, 18 February 2019 (UTC)
replies: text:  That's right. No mention of the phrase, "wave-particle duality." Just lots of stuff about particles acting like waves. QED. NRPanikker (talk) 20:59, 18 February 2019 (UTC)
thread_title:  Wave-particle Duality on Busy Roads