Eigenvalue problem with operators as matrix elements

AI Thread Summary
The discussion revolves around solving a specific eigenvalue problem involving a matrix with operators as its elements. The user seeks to find the eigenfrequency and eigenvectors, specifically questioning the dependence of the eigenvalue \(\omega\) on \(x\). Clarifications are requested regarding the notation, particularly the use of partial derivatives and the interpretation of \(\omega\). Participants emphasize the need for precise definitions and the implications of the problem's structure on the solutions for \(a(x)\) and \(b(x)\). The conversation highlights the importance of clear communication in mathematical problem-solving.
wil3
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Hello, I have a feeling that the solution to this question is going to be incredibly obvious, so my apologies if this turns out to be really dumb. How do I solve the following eigenvalue problem:

<br /> <br /> \begin{bmatrix}<br /> \partial_x^2 + \mu + u(x) &amp; u(x)^2 \\<br /> \bar{u(x)}^2 &amp; \partial_x^2 + \mu + u(x)<br /> \end{bmatrix}<br /> \begin{bmatrix}<br /> a(x)\\<br /> b(x)<br /> \end{bmatrix}<br /> =<br /> \omega(x)<br /> \begin{bmatrix}<br /> a(x)\\<br /> b(x)<br /> \end{bmatrix}<br />

where all x dependencies have been declared. I know the definition of the function u(x), but I need to solve for the eigenfrequency and eigenvectors.
 
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wil3 said:
Hello, I have a feeling that the solution to this question is going to be incredibly obvious, so my apologies if this turns out to be really dumb. How do I solve the following eigenvalue problem:

<br /> <br /> \begin{bmatrix}<br /> \partial_x^2 + \mu + u(x) &amp; u(x)^2 \\<br /> \bar{u(x)}^2 &amp; \partial_x^2 + \mu + u(x)<br /> \end{bmatrix}<br /> \begin{bmatrix}<br /> a(x)\\<br /> b(x)<br /> \end{bmatrix}<br /> =<br /> \omega(x)<br /> \begin{bmatrix}<br /> a(x)\\<br /> b(x)<br /> \end{bmatrix}<br />

where all x dependencies have been declared. I know the definition of the function u(x), but I need to solve for the eigenfrequency and eigenvectors.
I assume that you mean to find the function omega of x? You need to specify, because it's unclear what you want. Is your use of del indicating a partial derivative or a directional derivative. Be specific.
 
Typo in question: \omega should not depend on x. I want to solve for \omega, hence why I am calling this an eigenvalue problem. I'm not sure if getting w will also give a and b, like in a standard linear system.

\partial_x indicates a partial derivative, which is standard notation in physics for this sort of problem. But the problem would be identical if you wanted to interpret that as a directional derivative (both because the problem is one dimensional and because the subscript x would suggest a derivative in the x direction).
 
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