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Green's function expansion in a set of eigenfunction

  1. Sep 22, 2004 #1
    Hi! I encountered the problem that I need to decompose the Green function into a set of eigenfunction. Particularly, I have the free space Green function
    [tex] G(\vec r; \vec r') = \frac {e^{i k | \vec r - \vec r'|} } {4 \pi | \vec r - \vec r'|} [/tex]
    and I need to express it into series of cylindrical mode eigenfunctions
    [tex] \Psi ( \vec r; k) = H_m ( q r) sin( h z) e^{i m \phi} [/tex]
    [tex] k^2 = q^2 + h^2, h = \frac { \pi } {2 L} [/tex]

    here H - Hankel's function of the first kind.
    Eigenfunction forms a complete set, with discrete spectrum of eigenvalues q and h.
    I know that we can decompose the Green function into set of eigenfunctions, but I have the Green function for spherical representation, and eigenfunctions are from waveguide formed by two infinite plates parallel to each other. I couldn't find anything relevant about expanding the Green function into arbitrary set of eigenfunctions. Would appreciate any opinion or advice on the matter :)
  2. jcsd
  3. Sep 23, 2004 #2

    Dr Transport

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    Look in Jackson's Electrodynamics book, I believe that the solution can be found by applying either chapter 2 or 3's methods.
  4. Oct 4, 2004 #3
    i want notes about quantum dynamics(schrodinger,heisenberg and interaction representation or pictures of quantum mechanics)
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