Prove the operator d/dx is hermitian

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AI Thread Summary
The discussion centers around proving that the operator d/dx is not Hermitian. Participants clarify that an operator is Hermitian if it satisfies the equation <m|Ω|n> = <n|Ω|m>*. The user attempts to apply integration by parts to show the relationship between the integrals involving the operator and the functions, but struggles with the application. It is emphasized that the proof requires demonstrating that the integrals of the products of the functions and their derivatives do not satisfy the Hermitian condition. The conversation highlights the need for a clearer understanding of integration by parts in this context.
baldywaldy
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Hiya :) the title is meant to be prove it isn't hermitian

Homework Statement


Prove the operator d/dx is hermitian


Homework Equations


I know that an operator is hermitian if it satisfies the equation : <m|Ω|n> = <n|Ω|m>*


The Attempt at a Solution


Forgive the lack of latex , I have know idea how to use it and find it baffling.

the intergral of (fm* d/dx fn) dx = the intergral of fm* d fn
={fm* fn - the intergral of fn d fm*} between the limits x=infinity and - infinity.

This is where i get stuck. I just don't know where to go from here, like i said sorry for the lack of latex usage :(.

Thanks for the help :D
 
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Think of integration by parts.

ehild
 
I know intergration by parts but i just don't understand how to apply in this situation because there are two functions and an operator
 
d/dx f means that you differentiate f with respect to x. d/dx f = df/dx = f'

You have to show that \int{f_n f&#039;_mdx}\neq (\int{f&#039;_n f_mdx})^*

ehild
 
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