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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Understanding the relationship between wavelength and constructive interference distance in Cox and Forshaw's "clock" model
In Brian Cox and Jeff Forshaw's book The Quantum Universe, they introduce a pedagogical model where quantum particles are described by an array of "clocks" at each point in space. The length ...
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How does Schrodinger's cat experiment relate to black holes? [closed]
I was told recently that the particles that make up a black hole are in a state of superposition and I'm not sure about it if this is true then how?
I am aware that very little is known about black ...
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Quantum interference
I am new to quantum mechanics. Say we have a double slit experiment and we send in photons. Assuming a 1D scenario for simplicity. The intensity at the camera plane may be described by the following ...
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Why is amplitude not conserved in a beam splitter?
If a beam of light with average power $\langle P_\mathrm{in}\rangle$ (and electric field amplitude $E_\mathrm{in}$) is incident on a 50:50 beam splitter, the output is two beams of equal power $\...
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Conservation of energy in superposition of EM waves
Consider the energies of the following two situations.
An EM plane wave $\mathbf{E} = E_0\cos(kz-\omega t) \hat{x}$, $\mathbf{B} = \frac{E_0}{c}\cos(kz-\omega t) \hat{y}$. The energy density is given ...
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Sum of three distinct frequencies equal zero
I am reading Feynman lectures (https://www.feynmanlectures.caltech.edu/II_33.html) and trying to understand the reflection of light from a boundary. To arrive at the transmitted and refracted ...
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Why can't electron be in superposition of $2p$ orbitals?
This is a simplified version of the arguably overly-general question about orbitals I asked a couple days ago. As before, the underlying presumption is the way that (at least for purposes of chemistry)...
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Intuitive analysis of d'Alembert's solution to the 1+1D wave equation
Why is the general equation for a 1+1D wave a superposition of two wave travelling in opposite directions $$u(x,t)=g(x+ct)+h(x-ct),$$ suggests d'Alembert's solution of $$\frac {\partial^2u}{\partial t^...
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What are Schrödinger’s kittens?
In quantum physics, what are “cat states” and “kitten states”, and how are they different from each other?
(These terms are used in dozens of journal papers.)
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Surface and atmosphere radiative exchange
When considering the radiative exchange between the Earth’s surface (with high broadband opacity and ε~0.95), and the band emissions of the atmosphere, with an average of around 10% transmission, we ...
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Vibrating string at many frequencies at once [closed]
I understand standing waves . When it vibrates faster it pushes air faster higher frequency . What about a plucked string? Does different segments have their own standing wave as the string as a whole ...
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Superposition of light beams by $\pi$ phase differences [closed]
What happens if we prepare superposition of two monochrome sinusoidal beams of light which are exactly the same but have $\pi$ differences in their phases? getting nothing?!
$$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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