Sorry but it's wave particle duality again...

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https://www.nature.com/search?journal=nphys&q=wave particle duality&page=1

When people come to this forum enquiring about the concept of wave particle duality the usual advice seems to be based on the idea that the concept is outdated and has historical interest only.
The problem is that many of the people who make those enquiries probably look at other sources of information and many of those sources seem to suggest that wave particle duality is not outdated at all and is still being actively researched. A quick google search will show that to be the case. just one example of this can be shown by clicking on the link above.
It seems that people get contradictory information and that can only lead to confusion.
Thank you
 

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  • #2
PeroK
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:headbang:
 
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  • #3
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:headbang:

I'm not sure I like the implications of your post PeroK. I'm not sure what you mean but it's easy to interpret your post as being dismissive and somewhat rude.
Let me rephrase my post which is based on the possible reactions of people, not me, who come here for advice. Those people are often told here that wave particle duality is an outdated concept. That's fine and the people should be grateful for that advice. But those self same people often look elsewhere and find that duality is still being discussed. That can be confusing so what's wrong with me pointing that out?
 
  • #4
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That can be confusing so what's wrong with me pointing that out?

You've pointed it out before. And before that. And before that.

Time to move on.
 
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  • #5
Nugatory
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It seems that people get contradictory information.....
The problem of contradictory information on the internet is unfortunately beyond our power to fix.
and that can only lead to confusion.
Someone following the links in your google search will become unconfused when they see that the linked articles are not using the phrase "wave-particle duality" in the popular sense. If we do a broader search that includes popular sources, then the sad fact is that many of these popular sources are confusing. I don't have any better ideas than to explain that the popular sources are unreliable and to provide pointers to better explanations.
 
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  • #6
Demystifier
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It is my impression that the term "wave-particle duality" is used only by experimentalists as a means to make their technical experimental work more interesting to a wider community (that is, to sell it in high impact journals such as Nature Physics), and not by theoreticians who really want to better understand the principles of quantum mechanics.
 
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  • #7
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You've pointed it out before. And before that. And before that.

Time to move on.

Yes I have pointed it out before but my enquiry about duality being discussed elsewhere had been overlooked. In the previous thread I provided a link to Nature Journals which referred to duality. But the thread was then closed for moderation. I never did get any replies as to why such a prestigious journal should be amongst those numerous sources that referred to duality. The thread was eventually re opened but my link had been removed.I had been stopped in my enquiries then and now it seems you are trying to stop me by telling me to "move on".
 
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The problem of contradictory information on the internet is unfortunately beyond our power to fix.

Someone following the links in your google search will become unconfused when they see that the linked articles are not using the phrase "wave-particle duality" in the popular sense. If we do a broader search that includes popular sources, then the sad fact is that many of these popular sources are confusing. I don't have any better ideas than to explain that the popular sources are unreliable and to provide pointers to better explanations.
Thank you. A big problem with the Nature and other non pop science articles is getting access to them. Since they refer to duality in "the non popular sense" it might be helpful to get a definition of what duality actually is.
 
  • #10
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@Dadface does my post #6 make sense to you?

Yes post six does make sense and thank you. My main interest is experimental physics and most references I've seen to duality refer to experimental work.
 
  • #11
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Thank you. A big problem with the Nature and other non pop science articles is getting access to them. Since they refer to duality in "the non popular sense" it might be helpful to get a definition of what duality actually is.

Someone following the links in your google search will become unconfused when they see that the linked articles are not using the phrase "wave-particle duality" in the popular sense.

@Dadface, looking at the search result you post in #1, as far as I can see, the only hit you got that actually related to "wave particle duality" was the first hit, for a 2014 paper; the other hits are for individual words and not the full phrase. So why not look at that first hit to see what that paper is about?

Go to this page - https://arxiv.org/abs/1501.03713 - and you can download the full PDF via this link: https://arxiv.org/pdf/1501.03713.pdf

If you (and others in this thread) read the paper, you may be able to discuss whether and how it supports your claim that wave-particle duality, as such, is "still being actively researched."
 
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  • #12
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Yes post six does make sense and thank you. My main interest is experimental physics and most references I've seen to duality refer to experimental work.
Well, I am a theorist and I can say that wave-particle duality does not make much sense from a theoretical point of view. I hope that some experimentalist can help you more about the experimental perspective.
 
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  • #13
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Well, I am a theorist and I can say that wave-particle duality does not make much sense from a theoretical point of view. I hope that some experimentalist can help you more about the experimental perspective.

So what is your view then of these fundamental entities? Neither wave nor particle, or what. Just the mathematics, correct. What is particle, hydrogen atom maybe?
 
  • #15
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It is my impression that the term "wave-particle duality" is used only by experimentalists
This is also my take on it. I think it is sloppy language.

I had a theoretician colleague who would also cringe every time he heard someone talk about "quantum jumps."
 
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  • #16
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quote from your paper
"If any known interpretation of QM respects a kind of wave-particle duality, then it is the Bohmian interpretation."
I see a hint of contradiction with the myth statment.
1. What is your view of QFT then considering electron as zero dimensional.
2. Does BM consider electron as a lump or a Dirac delta.
 
  • #17
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1. What is your view of QFT then considering electron as zero dimensional.
2. Does BM consider electron as a lump or a Dirac delta.
1. I don't understand the question.
2. What do you mean by lump?
 
  • #18
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It is my impression that the term "wave-particle duality" is used only by experimentalists

I was trained as an experimentalist and I approve this message. There is much quantum hype.
 
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  • #19
vanhees71
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It's really annoying that particularly in Nature, which is a journal with a very high reputation, still admits the use of such sloppy language, but you can't help it. If I'd have been the referee, I had tried to fight against it. I've not yet reviewed articles for Nature, but for other journals it works.

Again, there's no need for wave-particle duality anymore since 1926, and one shouldn't use the phrase anymore. I think we have discussed that of course one can describe everything said in the first link in the search results in #1

http://www.nature.com/nphys/journal/v10/n4/full/nphys2931.htm

in terms of modern QED without any reference to a classical-particle picture. There's no other quantum which is less adequate described as a classical particle than the photon. It doesn't even admit to define a position observable etc. etc. We have discussed this indeed endlessly in this forum.
 
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  • #20
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Since they refer to duality in "the non popular sense" it might be helpful to get a definition of what duality actually is.
There is no rigorous definition. When someone who knows what they're talking about uses the term "wave-particle duality", they're generally making an informal reference to some position measurement - a particle is something with a reasonably well-known position. However, the phrase is pretty much meaningless when taken out of context.
 
  • #21
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Well, I have a feeling it's actually worse than just poor language. The Quantum Eraser experiments I recall looking at come off as culling the data after the fact when the fine print is read. This coupled with editorial comments on the verge of being misleading kind of clinch it for me. Just an opinion.
 
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  • #22
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It's really annoying that particularly in Nature, which is a journal with a very high reputation, still admits the use of such sloppy language, but you can't help it.
Nature will do almost anything which will increase their impact factor, and you can't help it.
 
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  • #23
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Well, I have a feeling it's actually worse than just poor language. The Quantum Eraser experiments I recall looking at come off as culling the data after the fact when the fine print is read. This coupled with editorial comments on the verge of being misleading kind of clinch it for me. Just an opinion.
Speaking of quantum erasers, you might be interested in my
https://arxiv.org/abs/1703.08341
Sec. 5.1.
 
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  • #24
vanhees71
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Well, I have a feeling it's actually worse than just poor language. The Quantum Eraser experiments I recall looking at come off as culling the data after the fact when the fine print is read. This coupled with editorial comments on the verge of being misleading kind of clinch it for me. Just an opinion.
Quantum eraser experiments have nothing to do with wave-particle duality. The one by Walborn makes this as clear as one can get. It uses polarization-entangled photon pairs and takes carefully a coincidence-measurement protocol, so that you can after the photons have been irreversibly detected on the screen, choose partial ensembles out of the full ensemble. Without choosing the partial ensemble, it's in principle possible to gain "which-way information", i.e., with which quarter-wave plate in the corresponding slit the photon has interacted. Choosing the one or the other partial ensemble, however leads to the impossibility to gain which-way information in addition, and an interference pattern appears. The one subensemble's pattern is shifted against the other such that both together lead to the full ensemble's non-interference pattern. This is all well understood from standard Quantum Optics. No old-fashioned notion of wave-particle duality is necessary.
 
  • #25
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I've always equated "shut up and calculate" with the positivist interpretation. The quantum eraser experiment all use data taken "in the past".
 
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