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The role of metric in the Wave Equation
The wave equation is often written in the form
$$(\partial^2_t-\Delta)u=0,$$
involving the Laplace-Beltrami operator $\Delta$. However, the Laplace-Beltrami operator $\Delta$ is defined only in the ...
2
votes
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Spherical wave as sum of plane waves
How can we do this computation?
$\iiint_{R^3} \frac{e^{ik'r}}{r} e^{ik_1x+k_2y+k_3z}dx dy dz$
where $r=\sqrt{x^2+y^2+z^2}$ ? I think we must use distributions...
Physically, it's equivalent to ...
