What is Wave-particle duality: Definition and 94 Discussions

Wave–particle duality is the concept in quantum mechanics that every particle or quantum entity may be described as either a particle or a wave. It expresses the inability of the classical concepts "particle" or "wave" to fully describe the behaviour of quantum-scale objects. As Albert Einstein wrote:
It seems as though we must use sometimes the one theory and sometimes the other, while at times we may use either. We are faced with a new kind of difficulty. We have two contradictory pictures of reality; separately neither of them fully explains the phenomena of light, but together they do.
Through the work of Max Planck, Albert Einstein, Louis de Broglie, Arthur Compton, Niels Bohr, and many others, current scientific theory holds that all particles exhibit a wave nature and vice versa. This phenomenon has been verified not only for elementary particles, but also for compound particles like atoms and even molecules. For macroscopic particles, because of their extremely short wavelengths, wave properties usually cannot be detected.Although the use of the wave–particle duality has worked well in physics, the meaning or interpretation has not been satisfactorily resolved; see Interpretations of quantum mechanics.
Bohr regarded the "duality paradox" as a fundamental or metaphysical fact of nature. A given kind of quantum object will exhibit sometimes wave, sometimes particle, character, in respectively different physical settings. He saw such duality as one aspect of the concept of complementarity. Bohr regarded renunciation of the cause-effect relation, or complementarity, of the space-time picture, as essential to the quantum mechanical account.Werner Heisenberg considered the question further. He saw the duality as present for all quantic entities, but not quite in the usual quantum mechanical account considered by Bohr. He saw it in what is called second quantization, which generates an entirely new concept of fields that exist in ordinary space-time, causality still being visualizable. Classical field values (e.g. the electric and magnetic field strengths of Maxwell) are replaced by an entirely new kind of field value, as considered in quantum field theory. Turning the reasoning around, ordinary quantum mechanics can be deduced as a specialized consequence of quantum field theory.

View More On Wikipedia.org
  1. nohtha

    B What is the nature of de Broglie matter wave? Is it longitudian or transverse?

    I just want to elaborate the wave nature of electron from davisson and germer experiment . there is resonance of energy (54 ev)provide to electron for which it show wave like behavior's. give some better explanation for this.
  2. RUTA

    Insights How Quantum Information Theory Solves “the only mystery” of Quantum Mechanics

    [url="https://www.physicsforums.com/insights/how-quantum-information-theory-solves-the-only-mystery-of-quantum-mechanics/"]Continue reading...
  3. Grelbr42

    I How Big Is a Photon? - Exploring Interference Experiments

    This YouTube video, with the same title I have given this thread, reports on an experiment. He sets up an interference experiment. The light source is a HeNe laser. The light passes through a beam splitter then through two paths. The shorter path being about 0.26 meters, the long one about...
  4. L

    B Does light propagate as a wave of little bullets?

    According to Einstein light would be a particle and a wave. So I infer that it propagates in vacuum in form of waves of little bullets (particles). This explanation is very insuficient. So tell me how do waves increase in size since it's made of little bullets (particles)... a wave gets...
  5. D

    B Wave-particle duality of atoms and molecules

    Hello ladies and gentlemen, On the website of Encyclopedia Brittanicca I read the article about wave - particle duality. The article says that the wave - particle duality is experimentally established for light, electrons and protons. However, i found other internet sources which say that the...
  6. alexandrinushka

    B Wave-Particle Duality -- When is it a wave and when is it a particle?

    In order to trigger this "interaction at a point as a particle" does an entity need to meet a certain criteria? Why doesn't any other entity on its way force this transition? Can the properties of this wave be altered? Thank you.
  7. Matty521

    I A quasi-analogy of wave-particle duality?

    One Major question I have about wave-particle duality of say a photon... Could we describe it like a rock falling vertically into a still pond. Around this point of contact we establish a circular wall which detects the contact of the wave. Two things are evident here: the rock keeps on moving...
  8. P

    I Article on photon wave-particle duality

    We all know that Feynman declared wave-particle duality as the central/only problem of quantum physics. Not sure how to evaluate a recent publication summary on this topic: https://sciencex.com/news/2020-11-wave-particle-duality-entanglement-customary-pitfalls.html Would like others take on...
  9. J

    B Mach-Zehnder Experiment: Wave-Particle Duality Demonstrated

    Can the essence o the Mach-Zehnder experiment be resumed as shown, to emphasize the analogy with the double-slit experiment? When the beams are brought together on a screen they form an interference pattern (no which-path inormation; wave behaviour). If the screen is removed and replaced by two...
  10. Lord Crc

    B Wave-Particle Duality Controlled by Single-Photon Self-Entanglement

    I stumbled over this[1] paper recently, in which they report of experimental evidence for the claim made in earlier work[2] that the amount of "waveness" V and "particleness" P of a photon is related to the amount of self-entanglement C via the equation V^2 + P^2 + C^2 = 1. I found it...
  11. A. Neumaier

    I Wave-particle duality revisited: Neither wave nor particle

    Jan Sperling et al., Wave-particle duality revisited: Neither wave nor particle, arXiv:1907.09836 From the abstract:
  12. Dante Meira

    B What is the size of a VHF photon?

    I read that electromagnetic radiation behaves both as particle and as wave, in what is called wave–particle duality. Given that the radio waves of VHF television have wavelengths from one to ten meters, what is the size of a "VHF photon"?
  13. J

    B Is wave-particle duality a result of the relativity theory?

    Have thought about this for sometime but couldn't get deeper. I have speculated that wave-particle duality is a direct result of the relativity theory. Especially it could arise from the factor of length contraction (dimensionality reduction). So far, the particle reality is based on various...
  14. ISamson

    B Light, Photons, Waves, Particles: Wave-Particle Duality....

    Me and my friend have recently (half a year ago) had a huge debate, between ourselves, about the wave-particle duality. We took sides in light being a particle or a wave. I was for particle he was for waves. At the end of a hot-filled week of arguing, the debate ended up with the acceptance of...
  15. J

    B Wave-particle Duality Help

    After reading on the basics of this & watching videos, here are some questions I can't help asking. When the wave is traveling in the room that is filled with air, will the photon interact with all the air molecules continuously collapsing the wave aspect? As I understand...
  16. G

    I Wave-Particle Duality of Electrons

    The wave-particle duality of light was demonstrated first with Thomas Young's 1801 Interference Experiment...and then more clearly with the Double Slit Experiment. Both of these were done with light (so photons). My question is -- How did we come to understand the same of electrons? Did we...
  17. LarryS

    I Wave-particle duality general question

    I just read the following paper that was written in 2014: https://arxiv.org/abs/1403.4687 It proposes that wave-particle duality and the momentum-position uncertainty (entropic) principle are physically the same phenomena. The paper was discussed at some length in this forum in the following...
  18. W

    Releasing Electrons with a color filter

    Homework Statement Simple question we have to answer: (Physics) How do I release the electrons from the cathode with a color filter? (The so called Photoelectric effect)Homework Equations none The Attempt at a Solution[/B] Here we have a conflict , the so called wave-particle duality, if...
  19. Tareq Naushad

    B How to make the wave collapse in double-slit experiment

    I successfully created the fringe pattern at home with a simple laser light and a black plastic sheet with two thin cut as double-slits. I then used two mobile phone cameras at two sides in hope that the wave function of light will be collapsed. But nothing happened i.e. the fringe remained...
  20. Peter99

    I Wave-particle duality: nature of wave-particle as it travels

    Hi, I'm trying to conceptualize the life of a particle as it travels through free space. I wish to start simple and then build from there. Speaking about the wave-particle duality that we observe in fundamental particles. Let's start with electromagnetic radiation (then move on to...
  21. amjad-sh

    I Wave-particle duality and localization

    I have read recently that the motion of an electron of momentum p must be described by the means of a plane waves :\psi(\vec r,t)=Ae^{i(\vec k \cdot \vec r -wt)}=Ae^{i(\vec p\cdot \vec r -Et)/\hbar} de Broglie hypothesis states that every particle of momentum p has a wavelength lamda. I will...
  22. mousheng xu

    Will detecting 1 of the 3 slits break the wave patterns?

    In a double slit experiment (say, of electrons), when putting a detector to examine the passing of electrons through one slit, the wave pattern of the electrons disappears and instead the particle pattern appears. The classical explanation is that an electron exists both as a wave and as a...
  23. M

    What Shows the Wave-Particle Duality of Light in the Compton Effect Experiment?

    Homework Statement What quantity measured in the Compton effect experiment show the wave-particle duality of light? Homework EquationsThe Attempt at a Solution the question is out of 2 marks and all I can think about is momentum is there anything I am missing or am i completely wrong?
  24. KiNGGeexD

    Wave-Particle Duality (QED)

    I have been reading Richard Feynmans Quantum Electrodyamics and quite early in the first chapter he asserts that Photons are particles. His reasoning that as you decrease the intensity of light incident on a photomultiplier the clicks which the multiplier make become less frequent but equally...
  25. F

    Wave-particle duality explanation?

    Hi, Is there a mathematical equation that for itself can explain, or be deducted from it the wave-particle duality? I mean something that connects that 2 concepts in physics equations? sorry if my english isn't very good.. PD: If you can recommend me a paper or a book that describes and...
  26. G

    Wave-particle duality and my non-physicist friend

    Hi, I'm a vet with an amateur interest in physics. In discussion with a friend about the usefulness of physics he stated that physicists had not even decided whether light was a wave or a particle. I said the following: 'The question of whether light is a wave or particle is not one which...
  27. G

    Is wave-particle duality a myth?

    Hi, This paper- http://arxiv.org/abs/quant-ph/0609163 - suggests (on p4) that the term 'wave-particle duality' is an incorrect description of the phenomenon, but then goes into a bit of heavy maths to describe the realities of it, so I'm left a little confused. Is my understanding correct when...
  28. S

    ? connection between uncertainty and wave-particle duality

    After reading these recent articles on proof of the theory that merges the "duality" of .. " The connection between uncertainty and wave-particle duality comes out very naturally when you consider them as questions about what information you can gain about a system" Can someone point me to a...
  29. B

    Wave-Particle Duality

    Homework Statement Calculate the de Broglie wavelengths of an electron with energy 120 eV ...Homework Equations lambda = h\p where p = sqrt(2*Me*E) The Attempt at a Solution E=1.6E-19*120ev.. Then sub into equation and I get 1.1E-10m for the wavelength, which is the answer quoted. The...
  30. aditya ver.2.0

    The Wave-Particle Duality of light and the laws of reflection

    I wonder how the wave particle duality property of light persists with the laws of reflection? How exactly is a photon directed in the same angle (i.e. the angle of incidence) by a particle as reflection while abiding through the quantum theory and the Raman Effect? Such as we throw an elastic...
  31. aditya ver.2.0

    On the Wave-Particle Duality property of light

    I just want to confirm a statement the - Light travels in the form of electromagnetic waves in open space, not particles, but converts to a particle while encountering an obstacle deserting its wave form. So is the statement correct or not? And does it persists any anomaly or exception while...
  32. L

    What waves in wave-particle duality according to de Broglie

    NON-LINEAR WAVE MECHANICS A CAUSAL INTERPRETATION by LOUIS DE BROGLIE "Since 1954, when this passage was written, I have come to support wholeheartedly an hypothesis proposed by Bohm and Vigier. According to this hypothesis, the random perturbations to which the particle would be constantly...
  33. Greg Bernhardt

    What is wave-particle duality

    Definition/Summary The double-slit (or 'two-slit') experiment clearly demonstrates that individual particles exhibit a wave-like behavior, in that an interference pattern can be shown to build up over time, despite the presence of only one particle in the experimental apparatus at any given...
  34. H

    Wave-particle duality confusion

    Hi, I am a high-school student who recently finished the chapter on QM. I thought I completely understood it, but when I started to look back at what I’ve learnt, then suddenly, nothing really makes sense. And one of the things I find really really hard is the nature of electrons. My...
  35. I

    Wave-Particle Duality and Particle Specific Identification

    I have been struggling with one simple question. How can one measure the momentum of a particle within a field without disrupting the entire field, all together? If the particle is under observation at at t_0, how is it verifiable that at t_1 the same particle is being observed? Obviously spin...
  36. ShayanJ

    Are Phonons Particles? Exploring the Wave-Particle Duality

    Phonons are said to be the result of the quantization of crystal waves.Let the function u=u_0 e^{i(\vec{k}\cdot\vec{r}-\omega t)} describe such a wave. Is it right to say that if we assume u to be the quantum mechanical wave function of a particle, that particle is a phonon? Thanks
  37. P

    Possible explanation for the wave-particle duality ?

    Hi everyone, today I had a thought coming across my mind when I woke up, and I think it might be an explanation for the particle-wave duality. Now, when we are talking about a particle, one thing that has to be mentioned is the uncertainty principle. If you divide space into equal volumes for...
  38. Islam Hassan

    QFT: Point-Like Particles vs Wave-Particle Duality

    Is there a (theoretical) partial or total inconsistency in QFT's postulate/premise/description of elementary particles as dimensionless, point-like objects with respect to the wave-particle duality nature of QM? This is in the sense that such description is *only* particle-like. Clearly, even...
  39. F

    Reason for wave-particle duality?

    Recently been thinking about the double slit experiment, and Schrodinger's cat thought experiment. And realized that quantum mechanics only applies to the atomic, and subatomic level of the universe as far as we know. And what's more that I realized that gravity does not play any significant...
  40. S

    Wave-particle duality in the Standard Model

    I posted this question in an another forum but I didn't receive any answers, so I'll post it here again: Do all the fundamental particles in the Standard Model (61 fundamental particles) exhibit wave-particle duality? From my understanding, a photon acts more like a wave than it does a...
  41. M

    Wave-Particle Duality: Double & Single Slit Experiments

    My initial understanding of the double-slit experiment was that the resulting interference pattern demonstrated that particles such as electrons behaved like a wave. However, if one of the slits was covered, then they reverted to their particle-like nature. However, the single-slit experiment...
  42. Hercuflea

    Quick beginner question on wave-particle duality

    For a given entity, what is the convention for determining whether it behaves as a wave or as a particle? I know that we generally treat neutrons as waves when they travel faster than .2c, but is there an "absolute" way of determining this for a general particle, or is there a wave-threshold...
  43. C

    Questions about wave-particle duality

    Please bear with me as I have been reading about quantum physics and, not being a physicist, I have some questions regarding the nature of wave-particle duality. First of all, according to the special theory of relativity a particle with a rest mass would need infinite energy to accelerate to...
  44. D

    LaTeX Observing Wave-Particle Duality in a Classical Experiment

    This is what's happening: (space after "-demonstrates wave particle duality") This is the surrounding code: \begin{multicols}{2} \section*{\centerline{Classical Experiment}} \begin{singlespace*} \begin{itemize*} \item demonstrates particle/wave duality \end{itemize*}...
  45. L

    Wave-particle duality and special relativity

    hi, i am in year 13 of school, so i would appreciate it if any responses to this question weren't too far over my head. saying that i have a fairly decent back ground knowledge of some of these ideas. so, we have learned about the whole lead up to deciding photons etc. are not waves or...
  46. C

    There is a high concentration of introductory material on wave-particle duality

    (A disclaimer: I'm not an expert, having genuine confusion) There is a high concentration of introductory material on wave-particle duality that claims that the uncertainty principle manifests itself identically to the behavior of waves in the macro world. This however appears to be in direct...
  47. bohm2

    Wave-particle duality at Macro scale?

    No-one is suggesting that this is exactly the same as the wave-particle duality that exists at the quantum scale (e.g. non-locality) but I thought these papers looking at the behaviour of “walking droplets” that can be seen at the macroscale were very interesting: Quantum mechanics writ...
  48. P

    Bohr Model and wave-particle duality

    I am currently studying wave-particle duality. However, at the moment I do not see how the Bohr Model is connected to this topic. I know that the Bohr Model failed to recognise various aspects of the atom and that it works only for single atoms e.g. Hydrogen, but what did it fail to do when it...
  49. H

    Wave-Particle Duality

    Homework Statement At what Kinetic energy will a particle's debroglie wavelength equal its Compton Wavelength Homework Equations DeBroglie λ = h/mv Compton λ = h/mc The Attempt at a Solution Setting the two equations equal to each other, I got v = c, then said KE = (1/2)mc^2...