Simple question concerning Hermitian operators

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    Hermitian Operators
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The discussion centers on the properties of Hermitian operators, specifically the relationship between the expression ##(\hat{H} \psi)^* \psi' = \psi^* \hat{H}^* \psi'##, where ##\hat{H}## is a Hermitian operator and ##\psi## is a wave function. It is established that Hermitian operators are self-adjoint, meaning ##H^* = H##, which allows for the manipulation of operators within inner products. The participants emphasize the importance of understanding linear maps in the context of wave functions and provide insights into the position representation of these operators.

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Nikitin
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Hi. This might sound like a stupid question, but is it, in general, true that ##(\hat{H} \psi)^* \psi'= \psi^* \hat{H}^*\psi'##? Here ##\hat{H}## is a hermitian operator and ## \psi## a wave function.

I.e. do they switch places even when not inside an inner product? I am aware of the fact that you can move hermitian operators around inside an inner product, i.e. <H X| Y> = <X | H Y>, but I am unsure as to why you can do that. Can somebody link me to some proofs that explain all this?

thanks.

edit: fixed mistake in my question..
 
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Nikitin said:
<H X| Y> = <X | H Y>

This is the definition of a self-adjoint operator so naturally a self-adjoint operator is going to fulfil it.

With regards to your original question, if you see the wave function simply as a function here you may be in trouble. Consider instead ##\langle \psi| H## as a linear map from the state space to complex numbers.

Writing down the inner product in position representation, you will get that the linear maps defined by multiplication with ##(H\psi)^*## and acting with ##\psi^* H^*## on any wave function before integration will give the same result (by definition of the adjoint, that H is self-adjoint gives ##H^* = H##.
 
arghh I forgot to put a function to the right of the expression I was asking about, sorry about that. It's fixed now. Anyway:

what is position representation? I'm not sure if I follow your explanation..
 
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