Questions tagged [superposition]
A basic principle of solutions of *linear* differential (often wave) equations, ensuring that the sum ("superposition") of two solutions is automatically a solution as well. Conversely, solutions (amounting to quantum states in quantum mechanics, since the Schrödinger equation is linear) can be represented as a sum of two or more other distinct solutions, and so can be Fourier/eigenstate resolved to enhance mathematical tractability.
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Vibrating string at many frequencies at once [closed]
I understand standing waves . When it vibrates faster it pushes air faster higher frequency . What about a plucked string? Does different segments have their own standing wave as the string as a whole ...
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Superposition of light beams by $\pi$ phase differences [closed]
What happens if we prepare superposition of two monochrome sinusoidal beams of light which are exactly the same but have $\pi$ differences in their phases? getting nothing?!
$$E_1+E_2 = A\cos(kx-\...
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Interference pattern when particles don't go through either of the two slits, but hit only the mid-portion between the slits and ricochet off! [closed]
'Is it possible to conduct a double-slit experiment in such a way that a series of single electrons/photons) hit only the mid-portion of the two-slits and ricochet off (without entering either slit)? ...
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When does a transition collapse to the final state?
I did my PhD research on device physics of optoelectronic devices. We take the square of
$\langle f| H_{int} |i\rangle $ as the photon absorption probability or the theoretical efficiency of a ...
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Why do Linear Combinations of Atomic Orbitals form *sufficient* approximations of molecular orbitals?
(Assuming no relativistic effects or electron-electron interactions for this question)
First: Am I correct in thinking that Linear Combinations of Atomic Orbitals (LCAOs) are generally good ...
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I don't understand Schrödinger’s Cat [closed]
The main issue I have with the whole "Schrödinger's cat" thing is that the cat has to be either dead or alive. Just because you don't know whether or not it's dead or alive doesn't mean it’s ...
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The relation between Maxwell's equations and the Superposition Principle
My lecturer told us that the statement of superposition has two parts to it:
The Principal of Superposition states that if a charge is placed in the vicinity of many charges, the resultant ...
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Mechanism of Energy Conservation if Two Phase-Offset Photons Sum to Zero-Amplitude [closed]
EDIT: I somehow didn’t notice a cross product sign error, that’s the actual answer to my question. If the two wavefronts have opposing propagation direction and electric field vectors at the time of “...
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Physical terminology for multiplying a wave by a negative number
In physics, given a function $f: \mathbb{R} \to \mathbb{R}$ representing some wave, if we multiply $f$ by a large positive number this might be called amplifying the wave, and if we multiply $f$ by a ...
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How do you find the envelope function for a superposition of two waves or more?
I am trying to determine the envelope function of a superposition of two waves. I will give a concrete example:
Let
$$ f(x, t_1) = \cos(2x + t_1) + \cos(2x + 2t_1) $$
Using a trigonometric identity, ...
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Reasoning for this equality in the Schrödinger equation [closed]
I was doing a question from a quantum mechanics exam from my university for the previous year when I got the following question:
Consider an electron in a one-dimensional square well potential:
$$V(x)...
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Regarding Obtaining Equivalent Resistance using superposition principle
I was working through the electric circuits handouts by Jhan Kalda and encountered the following problem
Now, I do know the standard way to solve such problems, i have seen that method in Wand and ...
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How many layers of superposition can exist?
I was studying quantum mechanics through MIT OpenCourseWare, and the professor explained that any wavefunction can be expressed as a linear combination of different eigenstates, also known as ...
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Stern-Gerlach Experiment with Initial Position Space Measurement
Suppose at time $t = t_0$ I have a spin-1/2 particle in the superposition state
$$
\chi(r,t_0) \otimes (\alpha|\uparrow\rangle + \beta|\downarrow\rangle),
$$
where $\chi$ is the position wavefunction ...
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Can someone help me figure out these superposition equations?
(Please note : while the reply below addresses some of my questions, not all of them have been answered yet. Further contributions are welcome...)
So, in the paper "Bright and dark states of ...
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