Questions tagged [wave-particle-duality]
Use this tag for questions relating to the "wave-nature of particles" or the "particle-nature of waves" as they are often discussed in quantum mechanics, where a single object has properties of both classical particles and classical waves.
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What is difference in dual nature of light and particles? [closed]
As We know that light shoaws dual nature or I would rather say that Sometime we can explain some phenomenon using wave analogy and other with particle nature(photon analogy). Phenomena like the ...
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Why doesn't Gaussian wavepacket broadening in position mean there will be a shortening in momentum?
Many sources that say in free broadening of a Gaussian wavepacket, the momentum uncertainty (I think defined in terms of the range of 'significant' momentum amplitudes) is time invariant even as the ...
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Can pure destructive interference be used to separate light waves and collapsed light particles?
In the double slit experiment we see that light waves can interfere with themselves to create interference patterns made of constructive and destructive interference. However, when we observe light ...
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Particle as wave, stable?
I've started reading about the wave-particle duality but, after a few steps, reached a dead end:
Schrodinger equation solutions for a free particle is a sum of terms of the form:
$$\psi(\mathbf{r}, ...
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How do wave particles have spin?
I am not a student nor a scientist. If a photon is a wave until it is measured somehow, how can it have a spin? A wave is a wave. Is spin simply a mathematical tag that we give to particles? Or do ...
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Elastic scattering violates energy conservation?
In our introductory solid state lectures, the professor described von Laue's$^1$ diffraction conditions making the assumption of elastic scattering, which states that the incoming and the scattered ...
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Does velocity make sense if it is small relative to the de Broglie wavelength?
What does it mean if a particle has, say, de Broglie wavelength of $100m$ and a velocity of $1 m/s$? Is it even possible to have such a setup? I don't see why not, since we can always slow the ...
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Is the Number of Photons Inversely Proportional to the Wavelength? [closed]
I was rearranging the equation for the energy of a wave in terms of the number of a photons in the wave, and velocity, and found that:
starting with:
$$
nhv=E
$$
$$
E/nh=v
$$
$$
E/nh=fλ
$$
$$
E=nhfλ
$...
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What is the significance of the de Broglie wavelength? [duplicate]
I have just learnt quantum physics in school and learnt the concept of wave-particle duality.
But I still have trouble understanding what the de Broglie wavelength is. What does it mean for a particle ...
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De Broglie wavelength of composite systems
Can the De Broglie wavelength of a composite system (like a molecule) be derived as opposed to being calculated from the composite mass?
EDIT:
@Dr jh, interesting relation you have derived. However, ...
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Single Planck $h$ constants
Planck developed his black body radiation theory assuming that atoms treated as simple harmonic oscillators can stay in states of very much defined energy. If normal frequency of such oscillator is $\...
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A wave or a particle?
Ever since I first read about the quantum eraser experiment, I was wondering: if after the "measurement" the wave function collapses and we can observe a particle - does that particle remain ...
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Why should the integral of wavefunction squared be normalized for a Quantum Object?
According to the statistical interpretation of Quantum Physics, a particle does not have a precise position regardless of any measurements. But then, the interpretation imposes another condition on ...
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What principle of quantum mechanics tells us that harmonic fluctuations of a field act like localized particles? [duplicate]
"Quasiparticles" are ubiquitous in condensed matter physics, e.g. magnons and phonons, and more generally all particles in quantum field theory are considered the elementary harmonic ...
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Is proton diffraction more difficult to obtain experimentally?
I was studying the phenomena of particle diffraction and saw that any particle can be associated to a de Broglie wavelength, given by $$λ=\dfrac{h}{p}$$
Experimentally, we commonly talk about the ...
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Does a quantum wave stretch out forever?
In learning about the duality of quantum particles, I wonder if a quantum wave stretches out into the distance, essentially forever? And if so, when a particle is observed, is it possible (but highly ...
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Davisson and Germer experiment
I was reading about the experiment that confirms the wave particle duality as we see a sudden rise in galvanometer which was explained as a phenomenon of constructive interference.
Is it possible that ...
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How is the equation for de Broglie wavelength actually derived?
I have seen the equation for de Broglie wavelength derived through equating Einstein's $E=mc^{2}$, and Planck's $E=hf$, using a substitution from $c=f\lambda$ to make things in terms of wavelength. ...
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How do electrons divide?
Electrons show a banded distribution at the end of a double-slit experiment set-up. This banded pattern shows that wave interference prevents many electrons from reaching areas where probability is ...
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How do subatomic particles have mass, velocity, spin etc if they are waves? [duplicate]
I don't think I understand the concept of sub-atomic particles very well. How can an electron or any sub-atomic particle have mass and spin if they are waves?
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'Why' is the Schrödinger equation non-relativistic?
The transition amplitude for a particle currently in one spacetime point to appear up in another point doesn't respect causality which becomes one of the main reasons to abandon non-relativistic ...
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How will detectors effect the inteference pattern in a double-slit experiment?
We know that if you put a detector at the slits in the double-slit experiment, no matter before slits or behind slits, it'll destroys the interference pattern and resulting chunk pattern (particles ...
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Many Worlds: What happens to the mass?
This question answers the conservation of energy in many worlds by stating that the overall energy of the system is still conserved by adding up the overall probabilities of and energies of the ...
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Why do we replace $c$ (speed of light) with $v$ in de Broglie's equation? [duplicate]
Deriving de Broglie's equation (as per my text and teacher) involves equating $E = mc^2$ with $E = h\nu$, where $\nu$ is the frequency.
It goes like :
$$mc^2 = h\nu$$
$$mc^2 = \frac{hc}{\lambda}$$
$$...
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Trying to prove Heisenberg's uncertainty wrong [duplicate]
Heisenberg’s uncertainty principle states that we cannot determine the position and momentum of a particle at a time. I think I have an idea to prove it wrong ( although I believe I must be wrong here)...
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How current is produced in photoelectric cell?
In photoelectric cells, a current is detected when photoelectrons reach the electrode on the opposite side of the tube after being emitted. But shouldn't current be detected when photoelectrons leave ...
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On particle diffraction and its relation to the statistical interpretation of the wave function
Particles can be diffracted due to their quantum nature and that is understood by their wave-like behavior. Clearly seen in e.g. plane wave solutions of the Schrodinger equation or a superposition of ...
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Two slits experiment with glitchy detector
In the double slit experiment, when we place a detector on one of the slits, the electrons will start to act like particles. When we unplug the detector they return to acting like waves.
What if our ...
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If light is considered a wave, then what exactly is a photon? [duplicate]
So according to google:
a photon is a particle that transmits light.
Ok, but light is considered a wave, not a stream of particles(I'm pretty sure that this is what Young's double slit ...
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Is the incident photon in a mirror, the same one that reflects? [duplicate]
I am considering the photon as a particle.
The incident energy may be equal to the reflected energy, but I would like to know if there is any theory or way of demonstrating that the incident photon ...
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Why does the De Broglie Wavelength influence the scale in which a nuclear reaction occurs?
In high energy accelerator collisions, why does the De Broglie wavelength of the incident particle affect the type of interaction it has with the target nucleus?
E.g. In 280 MeV proton, "direct ...
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Looking for a very cheap heuristic demonstration (in a few lines) of Heisenberg inequality
While I perfectly know the true demonstration of Heisenberg uncertainty principle (from the full QM machinery), I'm looking for a very cheap heuristic way of getting
$$\Delta x \, \Delta p \ge h, \tag{...
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Is there any upper limit for de broglie wavelength due to zero point energy?
We know that the lower the momentum a particle has the higher will be its de Broglie wavelength, so is there any upper limit to the de Broglie wavelength of electron or any other particle due to the ...
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${}$What is an electron? [duplicate]
I have been taught that an electron has a wave-particle duality nature and an electron behaves as a wave when traveling.
I do also know that a wave is some kind of vibration, either it be a vibration ...
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Waching particles go through the double slit?
Sorry in case this is a duplicate, I haven't studied physics or maths, and I can't find answers anywhere. The double-slit experiments are frequently explained online like the one here: https://www....
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What is the meaning when the expected value is equal to zero for a free particle?
Let there be a free particle with mass $m$.
At time $t=0$ it can be described as following wave packet:
$$ \psi(x) = \frac{1}{\sqrt{2a}} \Theta(a-|x|) $$
where $\Theta$ is the Heaviside step ...
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What is the wave function of a quantum particle? [closed]
What is the exact meaning of the wave function of a particle?
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Does the double slit interference pattern depend upon probability?
If the interference pattern depends upon the probability of the particles travelling through the slit then the intensity at any point on the graph must not be zero. But graphs show that the intensity ...
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Considered as a wave, shouldn’t a photon’s energy decrease with distance from its point of emission?
I'm referring to this https://physics.stackexchange.com/q/543059 question and its most voted answer.
If we view the photon as an electromagnetic wave, the field strength should diminish with distance,...
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Is the wavelength of matter proportional to momentum or uncertainty thereof?
I am confused about de Broglie waves and their relationship with the uncertainty principle. Both have similar formula and seem to be the same thing with a slight conceptual difference. De Broglie ...
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is there a minimum speed for particles for the double slit experiment?
I am working on some calculations and seems there must be a cutoff speed for each slit distance for the interference pattern. In other words, for a slit distance of “d” , by reducing the anode voltage ...
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De broglie frequency [closed]
The de broglie wavelength of matter particle is very low. Does that mean matter is associated with waves of high frequency? If so why can't we detect them?
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Why do photons follow specific path after reflection from a mirror surface if they can be emitted in any direction by electrons of mirror surface? [duplicate]
The electron absorbs the energy of photon(with specific frequency)and re-emits the photon.The photon can be emitted in any direction. So why do they get re-emitted in a specific direction after ...
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Which formulae should I use when calculating the frequency of an electron given its speed? [duplicate]
If I know the speed of an electron, how should I go about calculating its frequency?
For example, if the electron was travelling at $v$ $ms^{-1}$ there are two options I could take.
Calculate the ...
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Why are diffraction rings closer together when electrons travel at a greater speed in electron diffraction?
I know that at higher speeds the de Broglie wavelength decreases so the electrons diffract less, but does the fact electrons repel affect it in any other way?
What I was thinking was that since ...
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How does amplitude affect photon's intensity as a particle?
Considering the scenario were a photon acts as a particle, how does amplitude affect the photon?
Does it increase its intensity? How do you visualise this?
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Why is the force exerted by a light beam on a spherical object independent of the amount of light reflected or absorbed?
When a sphere of radius $r$ is placed in the path of a parallel beam of light of intensity $I$, the force exerted by the beam on the sphere is given by:
$$F=\frac{\pi r^2 I}{c}$$
I derived the ...
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Can elementary particles be explained adequately by a wave-only model?
I have been watching quantum mechanics documentaries and reading a layman's book called "The Quantum Universe". I believe I understand why the double slit experiments exclude a particle only model. ...
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How can an electromagnetic wave behave as a particle?
Light is an electromagnetic wave and it possess both properties of a particle and wave.
Looking at the image I can imagine how it behaves like a wave.
However, I'm not sure how it can behave like ...
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What is the connection between the Planck-Einstein Relationship and the Average Intensity of an electromagnetic wave?
This is probably a silly question, and likely reflects a poor understanding, in general, of electromagnetic radiation, but here goes anyway:
I have encountered two equations that I am struggling to ...
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