Solving for <E^2> of a non-stationary state of the QSHO

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SUMMARY

The discussion focuses on calculating for a non-stationary state of the Quantum Simple Harmonic Oscillator (QSHO) represented by the wave function Ψ = [βxe^(-3iωt/2) + e^(-5iωt/2)]. The textbook solution indicates that equals 6.17 ħ²ω², derived from the integral = ∫ Ψ*Ĥ²Ψ dx. The participant highlights a discrepancy in their calculations, noting that while the cross term ∫ Ψ1*Ĥ²Ψ2 dx is zero due to being an odd function, the term ∫ Ψ2*Ĥ²Ψ1 dx is not zero, suggesting a failure to eliminate time dependence as expected. This indicates a potential misunderstanding of the orthogonality of the states involved.

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hnicholls
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I have the following non-stationary state of the QSHO:

Ψ =
MSP14861g00452b9i950b850000666ab1heg86823ge
[
gif&s=25.gif
gif&s=25.gif
gif&s=62.gif
e −3iωt/2 +
gif&s=62.gif
[
gif&s=49.gif
]
MSP8371000i0f8f1dc4d9600003a38cih2f043h9c3
e −5iωt/2]

where β = mω/ħ

in calculating <E2>

The answer I see in the textbook is 6.17 ħ2ω2.

This answer suggests that in calculating <E2> = ∫ Ψ*Ĥ2Ψ dx

where Ψ is composed of the above two terms Ψ1 and Ψ2 (a linear combination of E1 and E2 of the QSHO) the cross terms need to be zero to eliminate the time dependence as reflected in the answer in the textbook.

This leaves us with the inside and outside terms

∫ Ψ12Ψ1 dx + ∫ Ψ22Ψ2 dx and calculating the sum of these inside and outside terms producing the answer in the textbook.

However, as I calculated the cross terms ∫ Ψ12Ψ2 dx is zero as it is an odd function, but ∫ Ψ22Ψ1 dx is not zero as it is an even function. This would not eliminate the time dependence and would not result in a non oscillating result as reflected in the textbook.

Am I missing something here?
 

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Sorry part of Ψ did not load

Ψ =
upload_2017-7-13_22-17-2.png
[
upload_2017-7-13_22-20-37.png
βx
upload_2017-7-13_22-21-56.png
e −3iωt/2 +
upload_2017-7-13_22-23-56.png
[
upload_2017-7-13_22-23-37.png
]
upload_2017-7-13_22-17-30.png
e −5iωt/2]
 

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