Quick question about bra-ket notation

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SUMMARY

The discussion centers on the application of bra-ket notation in quantum mechanics, specifically regarding the equation H |n> = E_n |n>, where H is a Hermitian operator and E_n is a real eigenvalue. The user confirms the validity of the relation

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  • Understanding of bra-ket notation in quantum mechanics
  • Familiarity with Hermitian operators
  • Knowledge of eigenvalues and eigenvectors
  • Basic principles of perturbation theory

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Homework Statement



On Wikipedia there is an article about perturbation theory. To understand something I need to understand the following relation. They say:

Homework Equations



[itex]H |n> = E_n |n>[/itex]

So:

[itex]<n| H = <n| E_n[/itex]

H is Hermitian.

So: Why is this?

The Attempt at a Solution



I don't know if this is valid.

[itex](H \cdot |n>)^\dagger = (E_n \cdot |n>)^\dagger[/itex]

[itex]\Leftrightarrow[/itex]

[itex]<n| H^\dagger = <n| E_n^\dagger[/itex]

And since H is Hermitian and E_n is real, I get:

[itex]<n| H = <n| E_n[/itex]

Is this how things work?
 
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That looks correct.
 
Looks fine to me too.
 

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