Proof that the linear momentum operator is hermitian

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The discussion revolves around proving that the linear momentum operator, Px, is Hermitian. A participant points out a sign error in the initial expression but notes it is corrected later. Clarification is sought regarding the condition that ensures the boundary term vanishes, specifically that the wave functions must be restricted to those that meet this criterion. The use of "distributional differentiation" is suggested as an alternative approach. The consensus is that if special wave functions are used, the solution appears to be valid.
Paul Black
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hello
i have to proof that Px (linear momentum operator ) is hermitian or not
i have added my solution in attachments

please look at my solution and tell me if its correct


thank you all
 

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There's a sign error in the last expression of the first page, but you "fixed" it in the next expression.

This looks OK to me, but of course you should explain why ##\left.\psi_b^*\psi_a\right|_{-\infty}^\infty=0##.
 
What is the domain of the linear momentum operator that you're looking at? You can't just look at arbirary wave functions, because then ##\psi_b^*\psi_a\vert_{-\infty}^{+\infty}## will not be zero. You need to restrict to special wave function which do have that property.

Another solution is that you use "distributional differentiation".
 
thank you for your answers
if i take a special function which satisfy the property then is my solution ok?
 
Yea, it looks OK to me.
 
ok thank you very much
 
Time reversal invariant Hamiltonians must satisfy ##[H,\Theta]=0## where ##\Theta## is time reversal operator. However, in some texts (for example see Many-body Quantum Theory in Condensed Matter Physics an introduction, HENRIK BRUUS and KARSTEN FLENSBERG, Corrected version: 14 January 2016, section 7.1.4) the time reversal invariant condition is introduced as ##H=H^*##. How these two conditions are identical?

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