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Someone needs to copy this poster's simplistic style, and use it to explain to me why Laplaces equation of electrostatic potential is solved with Bessel functions times an exponential times a sine/cosine wave (edit: in cylindrical coordinates).



Here's the answer: an exponential times a sine/cosine wave is what you already have in rectangular coordinates. The Bessel functions show up because they are the cylindrical coordinate equivalent of sine, cosine and exponential. "What does that mean," you say? It is quite simple, as sine, cosine, the exponential function and all Bessel functions are defined as the solutions to specific "fundamental" differential equations. The basic thread between solving Laplace's equations in any coordinate system is, you separate variables and break down the equations in other ways until you have factored them into a set of standard ("prime?" I don't know if that's a good word, I'm not a mathematician) DEs that somebody like Bessel has tabulated the numerical solution of.


I haven't done electrostatic potential yet, but I have been blogging for 13 years. Maybe you would enjoy one of my other articles.

I like this one: https://blog.plover.com/math/60-degree-angles.html


I suppose you've already looked at:

https://en.wikipedia.org/wiki/Cylindrical_harmonics

?


No, but that page has all the info that Jackson's Classical E&M textbook already explains.

I was being slightly facetious, but any average person will tune out a complete derivation after 15 integral signs, 50 terms, and 100 factors unless there is a pleasing narrative woven throughout the discussion.


Haha, I feel you!




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