A little question on the Helmoltz Greens Function

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SUMMARY

The discussion centers on the Helmotz Green's function, specifically the relationship between the Helmotz Green's function (G_h) and the Poisson Green's function (G_p). It is established that G_h = e^(ikr)G_p, where G_p is defined as -1/(4πr). A critical point raised is the confusion regarding the Laplacian operator applied to G_p, which yields δ^3(r) rather than zero, highlighting the singularity at r=0 as a key factor in understanding this discrepancy.

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davon806
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Homework Statement


I was a bit confused when reading my notes.After some derivation it states that G_h = e^(ikr)G_p,where
G_h = Helmoltz Green's function
G_p = Poisson Green's function = - 1 /(4πr)

By definition (D^2)(G_p) = δ^3 (r)
(D^2 = Laplacian)

Please see the attached
(D^2)(G_p) = 0 =/= δ^3 (r),Why?

Homework Equations

The Attempt at a Solution


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I didn't bother to check your work, but did you consider the fact that there's a singularity at r=0?
 

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