Wavefunction normalisation and expectation values

AI Thread Summary
The discussion focuses on verifying calculations related to wavefunction normalization and expectation values in quantum mechanics. The user seeks confirmation on their position expectation value, noting a mistake where a term incorrectly shifted from the denominator to the numerator. They express confusion over calculating the momentum expectation value without integrals, particularly regarding the units of their results. Suggestions include considering complex numbers in relation to expectation values and emphasizing careful integration for accurate results. The conversation highlights the importance of precise mathematical handling in quantum mechanics calculations.
MoAli
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Homework Statement


See Image, Sorry Its easier for me to attach images than writing all equation on the forum's keyboard!
Screen Shot 2016-12-11 at 15.53.06.png
I only need to check if I'm working it out correctly up to the position expectation value because I don't want to dive in the rest on wrong basis !

Homework Equations


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The Attempt at a Solution


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You need to try some latex. What you have is correct, except that right at the end in the expected value of ##x##, ##\alpha## leapt from the denominator to the numerator.

##\langle x \rangle = \frac{12}{13 \alpha}##
 
Yeah still trying to learn latex, anyway, where the question asks to prove momentum expectation value is zero without integrals I get stuck, I got <p^2> = \frac{12/h^2}{13 } which still doesn't make sense to me, the units don't work!
 
MoAli said:
Yeah still trying to learn latex, anyway, where the question asks to prove momentum expectation value is zero without integrals I get stuck, I got the \langle p^2 \rangle to be \frac{12h^2}{72}

Regarding ##\langle p \rangle## you might like to think about complex numbers and expectation values.

I haven't tried to calculate ##\langle p^2 \rangle## or ##\langle x^2 \rangle##. You just need to be careful with the integration.
 
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