Is \(x^k p_x^m\) Hermitian?

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The discussion centers on proving that the operator \(x^k p_x^m\) is not Hermitian, while the symmetrized operator \(\frac{x^k p_x^m + p_x^m x^k}{2}\) is Hermitian. Participants explore the validity of conjugating integrals and derivatives in the context of Hermitian operators. The key point raised is that when conjugating an integral, all terms must be conjugated, which results in a switch between the bra and ket states. The conclusion emphasizes the importance of correctly applying these conjugation rules to determine the Hermitian nature of operators.
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Homework Statement


Show that the operator x^kp_x^m is not hermitian, whereas \frac{x^kp_x^m+p_x^mx^k}{2} is, where k and m are positive integers.




The Attempt at a Solution



Is this valid?

<x^kp_x^m>^*=\left(\int_{-\infty}^\infty\Psi^*x^k(-i\hbar)^m\frac{\partial^m\Psi}{\partial x^m} dx\right)^*
=\int_{-\infty}^\infty\Psi^*(i\hbar)^m\frac{\partial^m(x^k\Psi^*)}{\partial x^m} dx \neq <x^kp_x^m>

That is, can you conjugate an integral by conjugating its integrand? Can you conjugate a derivitive by conjugating the function you are differentiating?

And assuming that you can, did I carry out the conjugation correctly?
 
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You can conjugate the integrand, however, you have to conjugate all of the terms. Basically what happens is that the bra and the ket switch, and the operator is conjugated.

\langle \phi | A | \psi \rangle^* = \langle \psi | A^* | \phi \rangle
 

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