All Questions
Tagged with wavefunction heisenberg-uncertainty-principle
114
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Uncertainity in position in 1D potential box
In a question of a usual 1D box for a particle between $-L/2$ to $L/2$ i had to compute $\Delta x$ and $\Delta p$ for the particle. The solution used the formulas-
$$\Delta x = \sqrt{\langle x^2 \...
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3
votes
1
answer
171
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Ground state of particle in a ring
In the ground state of a particle in a ring, the boundary conditions allow the particle to have energy equal to zero. This sounds that the momentum is completely defined and, according to the ...
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3
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540
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The Uncertainty in momentum and the de Broglie wavelength
I'd like to pose a straightforward question by providing a brief example to determine whether my current approach is correct or incorrect.
Imagine I have an electron confined within a box measuring $1\...
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120
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Does Group Velocity violate Uncertainty Principle?
I've recently begun studying Quantum Mechanics and went through the descriptions of phase and group velocities and the fact the group velocity or the velocity of the resulting wave envelope represents ...
- 339
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106
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How does shape of a wavefunction changes as it encounters a potential barrier?
A particle of mass and energy $E > 0$ in one dimension is scattered by the potential
below
If the particle was moving from $x = -\infty$ to $x= +\infty$, which of the following graphs gives
the ...
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3
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817
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Does perfect knowledge of momentum of a free particle imply that there is a finite probability of finding free particle anywhere in the universe?
In the case of a free particle, if you have perfect knowledge of its momentum, the uncertainty in its position becomes infinitely large.
Does this imply that there is a finite probability of finding ...
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203
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Deriving the Heisenberg uncertainty principle from the wave packet [closed]
How did we get the C-17, is it possible to derive the Heisenberg uncertainty principle from the wave packet?
could you recommend readings to help me understand this better.
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2
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277
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How are the standard deviation, expectation value, and uncertainty related for a wave function?
In my introduction to Quantum Physics class we're learning about wave functions and uncertainties (with a great deal of it being shown through graphical means). However, in the notes from my lecture I ...
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72
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What does "the range of reciprocal wavelengths" mean for a wave packet? (QM)
I'm learning about the derivation of the uncertainty principle via the addition of a finite number of sinusoidal waves of varying wavelengths and frequencies (basically, baby steps towards a Fourier ...
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17
votes
4
answers
3k
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Why does the Heisenberg uncertainty principle apply to particles?
This might be a slightly naive question, and if so I apologize, but I am currently a little confused as to why the Heisenberg Uncertainty principle should apply to particles, i.e. our system (say an ...
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379
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What does the $\Delta x $ in Heisenberg uncertainty principle actually mean?
In the textbook ''Concepts of Modern Physics -Arthur Beiser'' in chapter 3 section 3.7 where the book talks about the uncertainty princple
While illustrating the physics behind the uncertainty ...
- 301
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3
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218
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Intuitive and/or qualitative meaning of Heisenberg's uncertainty principle
I'm trying to figure out what the uncertainty principle really means, and I've arrived to construct this 'mental experiment': let's suppose to know with great precision the momentum of an electron (or ...
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159
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Why can a particle have both 0 and infinite momentum uncertainty?
I am a little confused by the meaning of this result. If I take a constant wave function $\phi_0 = \frac{1}{\sqrt{2a}}$ spaning over $(-a,a)$, I can convert this the momentum space:
$$\Phi(p) = \frac{...
0
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1
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85
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The connection between the Heisenberg Uncertainty Principle and wavefunctions
I have recently read Something Deeply Hidden by Sean Carroll, and in the book, he tries to sum up how the Heisenberg Uncertainty Principle can be found from just the way wavefunctions work, but I ...
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103
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Derivation Heisenberg Uncertainty
I know there have been many questions posted regarding the derivation of the Heisenberg Uncertainty. I do not want to derive its general form, but instead I would like to calculate its lower minimum ...
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