BELIEVE   ME   NOT!    - -     A   SKEPTIC's   GUIDE  

. . . as¹

I am using the conventional notation for $\Hat{\imath}, \Hat{\jmath}, \Hat{k}$ as the UNIT VECTORS in the x, y, z directions, respectively.

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. . . charge]:²

I know, I know, I am using the $\phi$ symbol for two different things. Well, I said it was the preferred symbol for a scalar field, so you shouldn't be surprised to see it "recycled" many times. This won't be the last!

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. . . on.³

These are rotten examples, of course - the first practical criterion for the variables of which any $\phi$ is a function is that they should be linearly independent [i.e. orthogonal ] so that the dependence on one is not all mixed up with the dependence on another!

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