Questions tagged [interference]
Interference describes different waves superposing to form a resultant wave of greater, lower, or the same amplitude. Normally, it involves interaction of waves that are correlated (coherent) with each other, either because they come from the same source, or because they have the same or nearly the same frequency. Interference effects can be observed with all types of waves, e.g., light, radio, acoustic, surface, or matter waves.
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Light wave interference on thin film
Let a point P exist just above the surface of a glass slab of thickness $L$.
Light is incident vertically on this slab. The light at point P, at some instant has phase angle $\phi$.
The refracted ...
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Superposition of waves and interference
For mechanical waves, Is the principle of superposition valid for waves that do not travel in the same plane ? For eg with one wave S1, travels along positive x-direction and another wave S2, is ...
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Interferene of Gaussian beams with different waists
We want to calculate the interference pattern of two Gaussian beams with different focal points. We use the basic formula for a Gaussian beam
$$ \vec{E}(x, y, z) = E_0 \vec{x}\frac{\omega_0}{\omega_z}\...
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Opera glasses and interference of light
One sunny day my kids asked me about the light circle (see photo below) they noticed on a small wooden bench in a dark room with no windows (there are just doors to other rooms and kids usually sit on ...
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Entangled electrons: no interference (Ballentine)
Ballentine's textbook presents an experiment with entangled electrons (page 271 of the pdf, problem 9.6) whose resolution of the "paradox" can be found in the chapter "solutions" (...
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Effect of thickening polariser on intensity pattern
I've performed an experiment where microwaves were sent through a polariser of varying thickness, composed of $11$ slits (width and spacing both $6$ mm).
To vary the thickness of the polariser, this ...
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Why does the placement of a lens effect the shape of the interference pattern in the Michaelson Interferometer?
Consider the simple Michaelson interferometer configuration below:
I'm working with this apparatus in lab, where we add an additional component (a bi-convex lens placed either between the light ...
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Is the interference pattern of an entangled particle affected by the measurement of it's pair far enough away to take into account special relativity?
I've been considering a theoretical setup for a quantum experiment where 2 particles are prepared with entangled spin. They are then moved far away from one another where particle B is next to Bob who ...
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Measuring coherence length with the Michelson Interferometer
In lab, I've been asked to measure the coherence length of a green-light laser source using a Michelson Interferometer. To do so, I configure the interferometer such that a circular fringe pattern ...
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What defines "minimal coherence" as a condition for the emergence of stationary interference in a chaotic wave field?
Consider the following observations:
A superposition of two electromagnetic waves with different frequencies will never produce visible interference patterns. Such waveforms will produce ...
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How can there be total destructive interference after a Wick rotation?
My question is exactly this one from Physics Forums, but I don't see any duplicates on SE and it doesn't seem to have gotten a clear answer there.
If the Wick rotation switches out the complex $e^{iS/\...
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Is this an accidental interference pattern?
I recently purchased this laser level. When I turned it on, I got excited when I noticed that it projected this interesting pattern on the wall:
Is this an interference pattern? I don't know much ...
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Poynting vectors of perpendicular intersecting waves
Let us assume that wave $E_a(x,t)=Ae^{i(kx-wt)}$ is propagating along the $x$-axis and that wave $E_b(y,t)=Be^{i(ky-wt)}$ is propagating along the $y$-axis. The magnitude of the Poynting vector $\...
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How does the intensity of light in a double slit experiment vary with the slit width?
I know this question has been asked quite a few times on the network but I still can't find a concrete answer. It's quite clear that intensity depends on the square of slit width in a single slit ...
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Phase estimation in contrast interferometry
In contrast interferometry, such as an atom interferometer using atoms in different momentum states or a fiber optic gyroscope (FOG), the signal in its simplest form can be written
$$S=\eta\left(1-\...
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How many fringes can pass by on a Michaelson interferometer?
A Michaelson interferometer is an instrument that most physics undergrads get to play with once or twice.
A beam splitter sends part of the light to each of two mirrors, the light returns, then hits ...
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Is interference of light a quantum phenomenon?
I am wondering whether the light interference is a quantum phenomenon. Or, alternatively, is there any interference in Maxwell's theory understood as a classical field theory?
The reason I am puzzled ...
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What is a 'good' coherence/correlation function for multimode spectra?
Following up on the question here and this answer in particular, I would like to pose the following question:
How to derive a formula for the coherence length of a multispectral source, such as a ...
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What is the equation that gives $a$ and $b$ of the elliptical polarization formed by two interfering linearly polarized waves?
Two linearly polarized light waves have amplitudes $A1$ and $A2$, the same wavelength, a phase difference of $p$, and an angle difference of $\theta$.
When two linearly polarized light waves with ...
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Interference of atomic orbitals: In what field do atomic orbitals oscillate? [closed]
I am learning molecular orbital theory for chemical applications. To understand why molecular orbitals can be antibonding, destructive interference aka out-of-phase interference of the orbital ...
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Magically reappearing fringes in Michelson interferometer for large path length differences?
I've built a simple Michelson interferometer from two mirrors and a beam splitter according to the following schematic:
Image source
My setup differs from the one in the publication in that mirror M1 ...
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Unsustained Interference Visuals
How does the interference (of coherent EM waves) that is not sustained look like? Kindly provide me with pictures or visual description. I tried searching the web but no avail.
People say fluctuations ...
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Interference of two colors
We know, from the age of Newton, or even before, that yellow is made by mixing red and green.
But we also know that yellow light is a particular wave having a particular frequency.
So how should we ...
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Can red and blue light interfere to make fringes in young’s double split experiment?
Supposing in young’s double split experiment, I cover one slit with red filter and the other slit with blue filter. The light coming out from the first slit would be red and the second slit would be ...
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Does light from incoherent source interfere?
We say that for us to observe interference we use coherent source but even if we use non coherent source light should still interfere, right?
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The action of $50:50$ quantum beam splitter
I have a question regarding the action of the $50:50$ beam splitter. According to Peter Knight's book, the action is
$$B=\frac{1}{\sqrt{2}}\begin{pmatrix}1 & i\\
i & 1
\end{pmatrix}.$$
However,...
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Absorption of a delocalized photon
I was thinking about the photon double-slit experiment recently, where a single photon is passed through two narrowly-spaced slits so that it delocalizes (passes through both slits), undergoes ...
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Why does Bragg's law consider only specular scattering for constructive interference?
My textbook only considers two-dimensional scattering, so I will stick to that. When explaining Bragg's law, it states that the incidence angle and the scattering angle must be equal so that all ...
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Diffraction of a laser composed of 2 monochromatic colours through a single slit / $N$ slits
To make the example simple, let's say we have a yellow laser that is the combination of 2 monochromatic lasers (green + red). In the example I will give, let's consider that the slits are narrow ...
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Young slits, are interferences possible without diffraction?
Is it possible to have a Young experiment with N slits producing interferences but no diffraction?
In my course, we have two formula's for the intensity at a certain point after the slits: one for ...
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Interferences between coherent sources facing each other
I don't understand how 2 coherent sources of longitudinal waves (i.e.: sound) facing each other have destructive interferences at certain fixed points between the 2 sources.
How come those points aren'...
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Thin Layer Interference: Why the OPD gets smaller with larger incident angle?
A little easily seeming geometric question, that tickles me:
On Wiki https://en.wikipedia.org/wiki/Thin-film_interference the derivation for the Optical path difference ($\textrm{OPD}$) in a thin ...
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Interference pattern of scalar wave around a Kerr black-hole
If a scalar field is scattered around a Kerr black-hole, its amplitude will be amplified, keeping the frequency of the wave constant. So consider two waves; one is coming out from the horizon $(r_* \...
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How do you create modeled coverage of obstruction based data?
I was wondering how it is possible to create a map of modeled coverage a CBRS radio provides in the real world with no auxiliary hardware? For reference this image is the modeled coverage a baicells ...
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Destructive interference of electromagnetic waves
So EM waves can have constructive interference and destructive interference right?
If two strips of EM wave intersect at a point in a destructive manner, would their propagation terminate?
If yes, ...
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Are interfering rays real in explaining the principle of least time in optics?
It is known that a ray of light chooses the path along which it will most quickly reach from point A to point B. Here there are questions about how light can choose something. To explain this, we say ...
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Eliminating sound vibrations by using destructive interference for sound waves
Can you eliminate sound vibration (when either it is audible sound, ultrasound or infrasound) by creating a destructive interference, but when both sources are in opposite sides?
Say, you have one ...
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What is going on in this Huygens Optical video? https://www.youtube.com/watch?v=SDtAh9IwG-I
https://www.youtube.com/watch?v=SDtAh9IwG-I
The following experiment is done.
A laser beam is split so that one path is 260 mm while the other path is 1300 mm. They are rejoined and sent to a detector....
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How does thin film increase the efficiency of solar panels? [duplicate]
The idea is that a thin-film on solar panels will cause destructive interference thus lowering the amount of reflected light and causing more light to be absorbed by the panel. However I do not ...
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What prevents cavity-enhanced neutrino detection?
The interaction between light and matter can be enhanced by trapping the light in an optical cavity. In a short Google research I didn't find an experiment trying to enhance neutrino-matter ...
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Interference pattern when the phase difference is 90°
We all know that entangled particles in polarisation will never make an interference pattern, in double slit setup with two orthogonal polarisers on either slits(say one slit with linear polarisers ...
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Book for thin film interference in optics
So i need to study a topic of optics which is thin film interference and i couldn't find a good book on the topic that would explain the necessary formulae derivations and contains rigorous ...
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Why doesn't a double slit act like a single slit?
Well, a single slit can be considered a continuous array of sources, and thus its spectrum is different than that of a double slit. But why is a double slit so different from a single slit if it is ...
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Do the photon and electron fields interact even if there is no absorption?
I am talking to a friend about why light travels more slowly through glass. We came to the understanding that it is a purely quantum mechanical effect caused by the electromagnetic field inducing ...
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How can Two particles in perpendicular S.H.M. interfere?
While studying the simple harmonic motion of a particle, I came across this concept of the interference of two particles in S.H.M. Everything made sense until it was about two mutually perpendicular ...
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In slit experiment: is it one wave function before and two wave functions after the split?
Forgive my round-about background to the question: I'm curious how the experiment "fires electrons slowly that interact with themselves"... I'm thinking that's just a simplification?
I feel ...
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Why the double slit pattern is a blurred image instead of two strips?
I am complete dilettante in physics, when i was first introduced to quantum mechanics by a You tuber named Arvin ash, he explained about the double slit experiment with quantum particles, there in his ...
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Fastest most accurate orientation measurement of an object while intermediary objects are involved to pass relative information
I am looking for the fastest most accurate way to have the orientation of an object measured optically while intermediary objects are involved between the source and the target. An example scenario ...
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Interference of beams after an interferometer
Well hello, i've come with a question regarding interference and when or when not path difference between two interfering beams of light matters or not. But lets begin with what I think I understand ...
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Is there any relationship between cross-terms in QFT and double slit experiment?
Suppose I have a fermion-fermion interaction with two channels $t$ and $u$, the matrix element is $\tilde M$ = $\tilde M_t + \tilde M_u$. Then when we square the matrix element, we have $$\sum_s\tilde ...
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