What is Wave particle duality: Definition and 48 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.

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  1. L

    B Quantum field theory and wave particle duality

    I recently watched this lecture "Quantum Fields: The Real Building Blocks of the Universe" by David Tong where the professor provides a succinct explanation of QFT in about 6 minutes around the midway mark. The main point being that there are fields for particles and fields for forces and the...
  2. Shreya

    What is the relationship between particles and waves in QED?

    "Everything is a particle whose position is predicted by a mathematical wave. Light is not a wave but is packet of energy whose position is predicted by the wave.The same goes for an electron. Interference pattern is a probability distribution of where we are likely to find an electron. When...
  3. Ebi Rogha

    I Measuring Photon Intrinsic Nature: Is Interference a Factor?

    I would like to know, how can we be sure this is not due to the influence/impact/interference of our measurement, not necessarily the intrinsic nature of photons? In most reference books, it seems it is a given and it is not discussed
  4. B

    B So can I use "wave particle duality?"

    Some sources say wave particle duality is very much a principal, others say it's oversimplified and not exactly true but still okay to use in order to explain things, and many say it's flat out wrong... so who's right? Can I say "wave particle duality" when talking quantum mechanics or no?
  5. A

    A What are Bohmian trajectories for a free electron?

    A free electron, or any other quantum particle, has an uncertain position/momentum, according to Heisenberg uncertainty principle. The squared amplitude of the wavefunction determines the probability of finding the electron at any point of the space. Accordingly, atomic orbitals are attributed...
  6. A

    I What is “quantized momentum transfer” and can it account for interference patterns?

    In https://www.sciencedirect.com/science/article/pii/S0378437109010401, the author claims that the interference pattern obtained in the double-slit experiment does not need a wave description of matter, and can be accounted for by the "quantized momentum transfer" from the slits to the electron...
  7. Isaac0427

    B Double slit and wave particle duality

    Just for my knowledge, not to confuse the OP, why would you say, for example, the double slit experiment does not show both of these properties in one measurement method? [Mentors' more: this thread was forked off from another thread]
  8. T

    Wave Particle Duality For Electrons and Photons

    Homework Statement Discuss the concept of the wave-particle duality for electrons and photons and include an equation which connects the wave like and particle like properties. Homework EquationsThe Attempt at a Solution So I am having trouble with how to word this question and generally...
  9. Dadface

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

    https://www.nature.com/search?journal=nphys&q=wave%20particle%20duality&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...
  10. 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...
  11. Dadface

    I Why does "wave particle duality" not exist anymore?

    I think I've asked this question here before but I'm still not clear about the answers. To reiterate, some experts on this forum seem to be of the opinion that wave particle duality doesn't exist anymore and this has been expressed in different threads and in different ways with certain...
  12. S

    B Wave particle duality - my visual/mental image

    I'm trying to get my head around some ideas in Quantum Mechanics, but I'm trying to find a visual/mental image of the ideas, so that I may, in some cases, understand a little better, if that's even possible. I have a mental image of wave/particle duality and I'd like to know if it's a valid...
  13. O

    I Doesn't wave duality for massive objects favor pilot-wave?

    It is well known that wave particle duality was also observed with large particles up to 10000 amu: Abstract of Paper : https://arxiv.org/abs/1310.8343 Doesn't that make pilot wave theory a more logical interpretation? For example it is easier than the whole material becoming a wave...
  14. N

    B Quantum Mechanics: Wave-Particle Duality Explained

    Hi, i am doing an introductory course in quantum mechanics (that would be equal to first two chapters in griffith's quantum mechanics). I have the doubt that what exactly do we consider in quantum mechanics. Let me say like the electron is a particle and when we will observe it will have a...
  15. C

    I Wave particle duality and phonons

    I was reading the thread about wave particle duality linked from the newsletter, and I noticed it said (to use my own words) that the conflict between wave and particle dynamics can be avoided by using operator dynamics instead. Unfortunately, in the case of phonons, I've never seen a...
  16. F

    B Is wave particle duality really wrong?

    Can all seasoned physicists please confirm if it is true that wave particle duality is really wrong as when Bill stated in the decoherence branches thread "This is a little different than what you will find in a beginner text becauise it doesn't use the wave particle duality which is wrong - but...
  17. Swapnil Das

    B Question about the nature of Gravitation

    Hello. Modern Physics explains Gravitation in two general ways: In accordance to the General Theory of Relativity, Gravitation is thought of as an effect of the curvature of space-time continuum. This results in the formation of the recently and famously detected Gravitational Waves. Quantum...
  18. Aurghyadip Kundu

    Bending of Light in diffraction? Is it actually possible?

    I know light has wave particle duality, I understand these two points very well, 1. Light moves as a probability function, taking all the possible paths at once. The alternate paths cancel themselves out, resulting in a particle-like combined motion. 2. When relatively close to an edge, some...
  19. G

    Wave Particle Duality: Understanding Single Slit Experiment

    In the single slit experiment, individual photons may be diffracted. The electric field of the em wave should accelerate charged particles in the screen (if it were a capacitor for example) but only one packet of energy exists. The photon may be absorbed after many wavelengths of light have...
  20. Y

    Wave particle duality: accept a new entity?

    Hi, I have always been presented with a description of photons (and electrons more recently) as being entities that at times behave like waves and at times like particles (and I understant that typically particle is a substitude word for small little solid object of mass). So I would like to...
  21. Ranvir

    EPFL's claim about wave particle duality

    Recent claims by scientists at EPFL suggesting that they somehow manged to photograph light simultaneously as a particle and as a wave raises more misconceptions than ever. The experiment on it's own is an excellent example of recent improvements in technological and experimental techniques, but...
  22. D

    De Broglie wavelength of an ant

    An ant of mass m = 1.80×10−6 kg goes through a hole of diameter D = 5.00 mm in a window screen which has thickness L = 0.600 mm. (a) What should be the approximate wavelength and speed of the ant for it to show wave behavior as it goes through the hole? I am not sure what should the...
  23. 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...
  24. C

    Physical meaning of a wave packet w/ respect to HUP&duality

    I'm a QM noob/newb trying to understand the physical implication of a wave packet, in my mind it is something like this: On the x-axis there is displacement (vibration), probability on the y. I Imagine stretching and compressing the wave packet. When I stretch it out, the amplitude must...
  25. J

    Does wave/particle duality apply to the full EM spectrum?

    My question relates to wave/particle duality. If light is regarded as possessing both wave like and particle like properties, and visible light is just part of the whole EM spectrum of radiation, is it correct to say that radio waves for instance, ( being themselves part of the whole spectrum...
  26. S

    De Broglie-Bohm pilot wave theory

    Are there any good books related to the not much popular De Broglie-Bohm pilot wave theory? There have been recent studies on dynamics of the walking droplets relation with pilot-wave dynamics to describe the motion of quantum particles.
  27. R

    Wave Particle Duality & Uncertainty Principle: Which Came First?

    Which of them comes first,(I mean the concept or the theory)? Did Heisenberg come up with the idea of uncertainty principle because of the discover of the wave particle duality? Thanks for paying attention~
  28. I

    Understanding wave particle duality

    I haven't studied physics, but I've had this thought in my head lately and I want to get it out. I'm hoping someone here can either help me understand this or set me straight if I'm on the wrong track. I've been mulling over wave particle duality in my head, and I realized that Einstein sort of...
  29. N

    Wave Particle Duality: Masses & Light Speed

    Do all masses show wave particle duality at near about speed of light?
  30. D

    What quantity shows the wave particle duality of light?

    What quantity measured in the Compton effect experiment shows the wave- particle duality of light? the momentum shows the wave particle duality of light. is this true? The Compton Effect is An increase in wavelength of X-rays or gamma rays that occurs when they are scattered.
  31. G

    Wave Particle Duality: Is It Mass-Energy Equivalence?

    I was thinking about wave particle duality, and it's always made out to seem so mysterious and paradoxical. But then it occurred to me that it might just be the same thing as mass energy equivalence, as waves are just energy and particles are 'mass'. Is this right or am I missing something?
  32. S

    Can wave particle duality be viewed at macroscopic scale ?

    can wave particle duality be viewed at macroscopic scale...?? ok so far we have discussed the wave particle duality in case of electrons of-course at microscopic level through the 1) interference phenomenon showing its wave behavior 2)photoelectric effect discussing its particle...
  33. G

    Wave Particle Duality Question

    Okay, so after a little research I think I have a fairly good understanding of wave particle duality. A wave function is just a wave of probability. You don't know where the particle will be until you measure it. Until then, the particle will be in superposition. While it is in superposition, it...
  34. G

    Calculating Electron Kinetic Energy, Velocity, Momentum, and Wavelength

    Homework Statement Some electrons are accelerated through a P.d. of 500 V. [e = 1.6x10^-19 C, mass of electron = 9.1x10^-31 Kg, h = 6.6x10^-34 Js.] 1. What is the kinetic energy of one of the electrons in eV? 2. What is the velocity of one of the electrons? 3. What is the...
  35. T

    Wave Particle Duality and its relation to the Wave Function

    Ok so from my understanding, the wave particle duality of matter is simply the fact that matter sometimes behaves as a wave and sometimes behaves as a particle. Ok, but I wonder if this has anything to do with the wavefunction. The wave function gives us the probability spread of matter at any...
  36. G

    Wave Particle Duality: Exploring Matter & Particle Properties

    What do we actualy mean a matter or particle having both wave and matter properties, and do the electrons occilate that means it has both up and down with the translational motion around the atom!
  37. D

    Wave Particle Duality: Magnifying Power of Electron Microscope

    Homework Statement Microscopes are inherently limited by the wavelength of the light used. How much smaller (in order of magnitude) can we "see" using an electron microscope whose electrons have been accelerated through a potential difference of 50,000V than using red light(500nm)...
  38. Q

    Wave Particle Duality: Diffracting Particles Explained

    Ok, if a particle is a wave and can diffract (e.g. through graphite sheet), I mean does the particle split into two or something, or does the particle somehow 'transform' into a wave? I am always inquisitive about this question.
  39. A

    Wave particle duality as applied to photon

    so basically a wave particle duality principle state that sometimes a "matter" would behave as a particle and a wave a another time. The was to reconcile this is through QM's statistical interpretation and the math construct is very obvious that such proposed matter is indeed a wave-particle in...
  40. Ahmed Abdullah

    What kind of wave is associated with particles , in wave particle duality?

    I know It is not EM wave. It is not probablity wave since probablity can never be negative. But I think De Broglie's wave length for particles (like electron) is derived using equation of mass-energy equivalence. It infers that this wave carries energy ;for this wave-length is same as...
  41. M

    Wave particle duality again(photons)

    I'm getting confused with the idea of probability(Schrodinger) waves and photons. Is the wave side of a photon a probability wave or an electromagnetic wave or both? In the 2 slit experiment with 1 photon at a time, it seems like a photon is described by a probability wave with a probability of...
  42. M

    Wave particle duality confusion

    I can't quite seem to understand wave particle duality. Every particle has a characteristic wavelength according to de Broglie. Is this the wavelength for the solution to the schrodinger equation for that particle? Take light for example, the wavelength of light corresponds the the wavelength of...
  43. A

    Wave Particle Duality: Exploring Wave Lengths & Objects

    I just learned formally about wave particle duality in the class today. wave length = plank's constant/momentum my teacher said that every moving object has a wave properties with wave length as described. So a baseball flying in a game would have a wave length of about 10^-30. Is it true...
  44. S

    Uncertainty Principle and Wave Particle Duality

    I don't get how the uncertainty principle is a direct consequence of wave-particle duality?
  45. A

    Wave particle duality as a research project

    Would this be a good idea for a research project, i.e as it has controversey in it, photoelectric effect verses Youngs double slit. im doing A-level, and this is a piece of coursework. thank you!
  46. T

    Proving Wave-Particle Duality of Light

    hey guys i was wondering if you knew any thing that helped to prove the wave-particle duality theory of light. any help would be greatly appreciated:smile:
  47. wolram

    Anomalies of wave particle duality

    http://arxiv.org/abs/quant-ph/0507178 Anomalies of Wave-Particle Duality due to Internal-Translational Entanglement Authors: Michal Kolar, Tomas Opatrny, Nir Bar-Gill, Gershon Kurizki Comments: 4 pages, 3 figures We predict that if internal and momentum states of the interfering...
  48. DaveC426913

    Wave particle duality & double slit

    I've been puzzling over the two-slit experiment. There's an alternate setup where you use lasers and prisms. [A laser beam is split with a half-silvered mirror/prism. Photons take one path or the other and hit one of two detectors. We arbitrarily insert a converging mirror/prism near the end...