The expected value (or mean) of X

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Discussion Overview

The discussion revolves around obtaining the expected value of a variable \( x \) in momentum space, specifically within the context of quantum mechanics. Participants express a desire for a derivation or solution rather than just the result.

Discussion Character

  • Homework-related
  • Technical explanation

Main Points Raised

  • One participant asks how to obtain the expected value of \( x \) in momentum space.
  • Several participants note that the original poster seems to have the result but lacks the derivation or complete solution.
  • There are suggestions that textbooks should provide a derivation, and if not, resources can be found online.
  • A specific online resource is shared as a potential reference for obtaining the position operator in momentum representation.

Areas of Agreement / Disagreement

Participants generally agree that a derivation is needed, but there is no consensus on the availability of such derivations in textbooks or online resources.

Contextual Notes

Participants express limitations in their current resources, noting that their textbooks provide only results without derivations. There is also an acknowledgment of the need for a complete solution.

peace
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hi. How to obtain the expected value of x in the momentum space ?
2019-10-19 12_36_45-Quantum.Physics.3rd.Edition (3) - WinDjView.png
 
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Looks like you have answered your own question.
 
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PeroK said:
Looks like you have answered your own question.
I only have the result. But I don't have the perfect solution to tell me how to achieve that. I'm looking for a solution.
 
peace said:
I only have the result. But I don't have the perfect solution to tell me how to achieve that. I'm looking for a solution.

Whatever textbook you are learning QM from ought to have a derivation. If not, you should be able to find one online.
 
PeroK said:
Whatever textbook you are learning QM from ought to have a derivation. If not, you should be able to find one online.
In my textbook only the result has been written, and not the complete solution.
Yet, yes, you are right. I search for a complete solution online.
 

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