Quantum Mechanics problem: Determine the value of the constant

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SUMMARY

The discussion focuses on solving a quantum mechanics problem involving the canonical quantization relation and the commutator's connection to the identity. The problem requires proving that the sum operator of the squared matrix elements |< E_n | X | E_0 >|^2 equals a constant, where E_0 is the energy of the eigenstate | E_0 >. The Hamiltonian is given as H = P/2m + V(X). Participants emphasize the importance of understanding the commutator [H, X] in relation to the problem.

PREREQUISITES
  • Understanding of quantum mechanics principles, specifically canonical quantization.
  • Familiarity with Hamiltonian mechanics and the form H = P/2m + V(X).
  • Knowledge of commutators and their significance in quantum theory.
  • Ability to manipulate matrix elements in quantum states.
NEXT STEPS
  • Study the properties of commutators in quantum mechanics, particularly [H, X].
  • Learn about the implications of the canonical quantization relation in quantum systems.
  • Explore the derivation of matrix elements in quantum mechanics.
  • Investigate the role of eigenstates and eigenvalues in quantum theory.
USEFUL FOR

Students and researchers in quantum mechanics, particularly those tackling problems involving Hamiltonians and commutation relations. This discussion is beneficial for anyone seeking to deepen their understanding of quantum operators and their mathematical implications.

Ineedhelpimbadatphys
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Homework Statement
The problem states work for word.

Using canonical quantization relation, prove that
sum operator ((E_n -E_0)) |< E_n | X | E_0 >|^2) = constant

Where E_0 is the energy corresponding to the eigenstate | E_0 >. Determine the value of the constant. Assume the hamiltonian had a general form H = P/2m +V(X)

Hint: One way to proof this is to think how [H, X], X] is connected to the obove identity.
Relevant Equations
all equations i have are in the statement.
I have no idea where to start with this problem. I am interested in any hints, or ways to proof this. But i would especially like to know how the commutator is connected to the identity.
 

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Please, everyone, be respectful of poster asking for a hint about one specific aspect of this problem.
 
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Ineedhelpimbadatphys said:
Homework Statement:: The problem states work for word.

Using canonical quantization relation, prove that
sum operator ((E_n -E_0)) |< E_n | X | E_0 >|^2) = constant

Where E_0 is the energy corresponding to the eigenstate | E_0 >. Determine the value of the constant. Assume the hamiltonian had a general form H = P/2m +V(X)

Hint: One way to proof this is to think how [H, X], X] is connected to the obove identity.
Relevant Equations:: all equations i have are in the statement.

I have no idea where to start with this problem. I am interested in any hints, or ways to proof this. But i would especially like to know how the commutator is connected to the identity.
What is ##< E_0 \mid [H,X],X]] \mid E_0 >##?

-Dan
 
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Thank you so much. I did actually manage to figure it out. I had tried calculatibg that, and got stuck at < E_0 | XHX | E_n > and assumed I was wrong.

After seeing this, I just kept trying and got it. thank you.
 
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