Ground State of the Simple Harmonic Oscillator in p-space

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SUMMARY

The discussion focuses on the ground state of a one-dimensional simple harmonic oscillator (1DSHO) and the application of the momentum operator p in terms of the annihilation (a) and creation (a†) operators. When the momentum operator is applied to the ground state |0⟩, it results in the first excited state |1⟩, represented mathematically as p|0⟩=i√(ħmω/2)|1⟩. The probability density in momentum space is derived using the Fourier Transform, yielding the expression |\Phi(p,t)|²=2√(πħ/mω)e^(-p²/(ħmω)).

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  • Understanding of quantum mechanics principles, specifically the simple harmonic oscillator.
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  • Knowledge of Fourier Transforms and their application in transitioning between position and momentum space.
  • Basic proficiency in manipulating quantum state notations, including eigenstates and probability densities.
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Homework Statement


A particle is in the ground state of a simple harmonic oscillator, potential → V(x)=[itex]\frac{1}{2}[/itex]mω[itex]^{2}[/itex]x[itex]^{2}[/itex]
Imagine that you are in the ground state |0⟩ of the 1DSHO, and you operate on it with the momentum operator p, in terms of the a and a† operators. What is the eigenstate? Then, how would you represent this operation in terms of a probability density in momentum space?

Homework Equations


p=i[itex]\sqrt{\frac{\hbar m ω}{2}}[/itex](a†-a)
Fourier Transform, x→p-space

The Attempt at a Solution


p|0⟩=i[itex]\sqrt{\frac{\hbar m ω}{2}}[/itex]|1⟩
So now the particle is in the first excited state of the SHO

But I don't understand the next part of the problem. How can I represent this terms of probability density in p-space?

I can perform the Fourier Transform and find that,

[itex]\Phi[/itex](p,t)=[itex]\sqrt{2}[/itex]([itex]\frac{\pi \hbar}{m ω}[/itex])[itex]^{\frac{1}{4}}[/itex] e[itex]^{\frac{-p^{2}}{2 \hbar m ω} - \frac{i t ω}{2}}[/itex]

And the probability density is,

|[itex]\Phi[/itex](p,t)|[itex]^{2}[/itex]=2[itex]\sqrt{\frac{\pi \hbar}{m ω}}[/itex] e[itex]^{\frac{-p^{2}}{\hbar m ω}}[/itex]

I don't believe I understand what this part of the question is asking. Any suggestions/ideas would be greatly appreciated.
 
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It doesn't make sense to me either. Is that the problem statement exactly as it was given to you?
 
Yes. Word for word.

Maybe it is supposed to be something like; "Find the expectation value of p...and then do the same thing in p-space."
But that seems too simple and we've already covered that. The p operator in p-space is just p.
 

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