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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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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Can two semi-infinite plane waves undergo perfectly constructive interference?
This is building off of a question I asked here.
When discussing the linked problem with some friends, the consensus seemed to be that the reason two identical semi-infinite plane waves cannot ...
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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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Superposition at $\pi/4$ phase-offset of elliptically polarised light
in an earlier question, i asked if elliptically-polarised light could be superimposed in a way that allowed the vector(s) $E$ (the jones vectors) to make sense:
superposition of elliptically polarised ...
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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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Can the equation of total maximum amplitude $A_n=\sqrt{A_1^2+A_2^2+2A_1A_2\cos(\Delta\phi)}$ be used though the waves are not in the same line?
Let $S_1$ and $S_2$ placed in the same point be the source of two waves which are propagating in the same line, also the phase differernce between the two waves $\Delta\phi=0$. Equation of the two ...
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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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How can states be added linearly in a projective Hilbert space?
If you have a Hilbert space $\mathcal{H}$, you can make a projective Hilbert space by modding out by the $U(1)$ group action of multiplying by a phase, $\mathcal{H}/U(1)$.
While we usually talk about ...
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Light Spectrum - Sum of Waves or Collection of Waves
I am wondering about the spectrum of light that is often shown pictorially as a distribution of power, say, from sunlight. My question is: does this indicate that each wave of light contains all of ...
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Energy of a Point at different times in a Standing Wave
Two waves traveling in opposite directions meet to Produce Standing Waves.
At Nodes
The displacement of one wave is +x and for the other wave, it is -x. Both of which cancel to produce a Node. At this ...
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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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