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In this article, researchers have used electrons to image light as both particle and wave at the same time.
https://phys.org/news/2015-03-particle.html
https://phys.org/news/2015-03-particle.html
Imaging of Light as a Particle and a Wave
In summary, the researchers used electrons to image light as both particle and wave at the same time. It appears that the electron responds to reactive as well as radiated fields, which supports the idea that it is acting as a true sensor for photons. However, it is still not clear whether photons actually are particles or waves.
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The original article:
https://www.nature.com/articles/ncomms7407
https://www.nature.com/articles/ncomms7407
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tech99
Science Advisor
Gold Member
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If we use an electron as a sensor, it will respond to reactive as well as radiated fields. It appears to react to the evanescent fields around thr wire. So is it acting as a true sensor for photons?
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It's soooooooo sad! Planck once said that old-fashioned theories in physics die out by people believing in them passing away. That seems not the case with the wrong pictures given in the introductory lectures and in popular-science writing.
What's indeed shown by this experiment is that plasmon modes of the em. field are quantized. That's all. There's no particle picture for photons proven ever. Photons cannot even by localized, because they do not admit the definition of a proper position operator to begin with. This is true even for free photons, let alone for cavity photons or plasmon modes, as investigated here. The Nature article is pretty clear on what's measured (and it's open access!).
What's indeed shown by this experiment is that plasmon modes of the em. field are quantized. That's all. There's no particle picture for photons proven ever. Photons cannot even by localized, because they do not admit the definition of a proper position operator to begin with. This is true even for free photons, let alone for cavity photons or plasmon modes, as investigated here. The Nature article is pretty clear on what's measured (and it's open access!).
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What is the ##R_0## of belief in wave-particle duality? Can it be properly treated or vaccinated against?vanhees71 said:
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It can be properly treated by just teaching modern quantum theory right away. In the next semester I've to teach my teachers students quantum mechanics, and I'll start my manuscript with a longer qualitative chapter on this didactical problem. I think, it's high time to make particularly future teachers aware of all the bad didactics in the introductory chapters of textbooks.
Of course, I surveyed the existing (German) literature on "Quantum Mechanics for teachers students", and I was shocked that the books provided utterly wrong pictures about quantum theory. Particularly all start with photons, which is the most complicated real-world quantum you can discuss. Allready free photons cannot be adequately discussed without a quite thorough analysis of the Poincare group, and unfortunately there's no time to teach this in this three-semester theory course. Nevertheless, on a qualitative level, one can describe all the modern single-photon experiments correctly without "drawing" the wrong picture of photons as "pointlike particles". One of the textbooks (there's even an English translation: it's Pade, Quantum Mechanics for Pedestrians, Springer 2014, 2 vols) which in principle is a very nice book, discussing modern applications of quantum theory on a level, which is well suited for this target group of students, using discrete-observable examples like spin and polarization states particles or photons etc., discussing Bell inequalities, entanglement, and all that. Hoever, I cannot recommend this book without a bad consciousness, because it's all wrong in its qualitative explanations. Rather than being careful to explain photons in a way of what's really observed and what comes out from the proper analysis of the Poincare group (which of course you cannot give to this target group; it's usually not even fully treated in BSc/MS lectures on QED, because you'd need an entire semester for the mathematics of the Poincare group rather than discussing real physics problems). On this qualitative level you can however still explain it correctly by sticking to what's observed and then just telling the students what comes out of the proper treatment within modern QED.
Of course, I surveyed the existing (German) literature on "Quantum Mechanics for teachers students", and I was shocked that the books provided utterly wrong pictures about quantum theory. Particularly all start with photons, which is the most complicated real-world quantum you can discuss. Allready free photons cannot be adequately discussed without a quite thorough analysis of the Poincare group, and unfortunately there's no time to teach this in this three-semester theory course. Nevertheless, on a qualitative level, one can describe all the modern single-photon experiments correctly without "drawing" the wrong picture of photons as "pointlike particles". One of the textbooks (there's even an English translation: it's Pade, Quantum Mechanics for Pedestrians, Springer 2014, 2 vols) which in principle is a very nice book, discussing modern applications of quantum theory on a level, which is well suited for this target group of students, using discrete-observable examples like spin and polarization states particles or photons etc., discussing Bell inequalities, entanglement, and all that. Hoever, I cannot recommend this book without a bad consciousness, because it's all wrong in its qualitative explanations. Rather than being careful to explain photons in a way of what's really observed and what comes out from the proper analysis of the Poincare group (which of course you cannot give to this target group; it's usually not even fully treated in BSc/MS lectures on QED, because you'd need an entire semester for the mathematics of the Poincare group rather than discussing real physics problems). On this qualitative level you can however still explain it correctly by sticking to what's observed and then just telling the students what comes out of the proper treatment within modern QED.
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Maybe it's just the difference between science and journalism. It seems strange to me, having learned QM without the wave-particle duality, that it's still strongly promoted, apparently.
Perhaps it's part of "selling" the subject. Like the Scottish Tourist Board promoting the Loch Ness Monster!
Perhaps it's part of "selling" the subject. Like the Scottish Tourist Board promoting the Loch Ness Monster!
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It's not strongly promoted anymore. It has been shown over 90 years ago that there's no wave-particle duality but a consistent mathematical description of quantum phenomena that so far withstood the hardest tests by experiment ever. That's why I find it so sad that people seem to think they still have to use outdated theories to introduce the subject to students. I'm not so much talking about science journalists, who are excused a bit, because they have to write in a way to generate buyers of their newspaper and clicks on their online sites. One must not expect too reliable information from science journalists. Often I don't understand at all what they want to say, and I have to go to the scientific publications they write about to understand it.
What I'm really angry about is that new textbooks are written, particularly with an emphasis in didacticts in the sense to simplify the theory such that physics-minor students can easily understand the essence, which are plain wrong in the picture they convey about QT. It's the more sad, because that's not even necessary to make the subject simple enough!
E.g. you can explain the Mach-Zehnder experiment with single photons without ever relying on a naive and plain wrong particle picture of photons. Even emphasizing the localizability of photons which is impossible from first principles mathematically in such books is a sin!
What I'm really angry about is that new textbooks are written, particularly with an emphasis in didacticts in the sense to simplify the theory such that physics-minor students can easily understand the essence, which are plain wrong in the picture they convey about QT. It's the more sad, because that's not even necessary to make the subject simple enough!
E.g. you can explain the Mach-Zehnder experiment with single photons without ever relying on a naive and plain wrong particle picture of photons. Even emphasizing the localizability of photons which is impossible from first principles mathematically in such books is a sin!
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kent davidge
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@vanhees71, how would you classify Weinberg's books? They are good in qualitative explanations?
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Which books exactly? All textbooks by Weinberg are simply master pieces (I know, Gravitation and Cosmology, 3 vols. Quantum Theory of Fields, Cosmology, and Lectures on Quantum Mechanics), but they address advanced physicists at the advanced graduate-student level and do not bother themselves to much with introductory qualitative explanations necessary at the more introductory level.
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kent davidge
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Thanks
vanhees71 said:
These
What is the concept of "Imaging of Light as a Particle and a Wave"?
The concept of "Imaging of Light as a Particle and a Wave" is based on the dual nature of light, which means that it exhibits both particle-like and wave-like properties. This concept is also known as wave-particle duality and is one of the fundamental principles of quantum mechanics.
What evidence supports the dual nature of light?
The evidence for the dual nature of light comes from various experiments such as the double-slit experiment, which showed that light behaves like a wave when passing through two narrow slits and creates an interference pattern. The photoelectric effect is another experiment that supports the particle nature of light, as it demonstrated that light can also behave as discrete packets of energy called photons.
How is the imaging of light as a particle and a wave used in scientific research?
The imaging of light as a particle and a wave is used in various fields of scientific research, such as optics, quantum mechanics, and photonics. It helps scientists understand the behavior of light and its interactions with matter, which is crucial for developing technologies like lasers, optical communication, and medical imaging.
What are the implications of the dual nature of light in our understanding of the universe?
The dual nature of light has significant implications for our understanding of the universe. It challenges our traditional view of particles and waves as fundamentally different entities and shows that they are two sides of the same coin. This concept also plays a crucial role in the development of quantum mechanics, which has revolutionized our understanding of the microscopic world.
Can light be both a particle and a wave at the same time?
Yes, light can exhibit both particle-like and wave-like behavior simultaneously, depending on the experimental setup. This is one of the most intriguing aspects of the dual nature of light and is still being studied by scientists to gain a better understanding of this phenomenon.
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