Undergrad Define inner product of vector fields EM

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The inner product of two vector fields, F(r) and G(r), in electromagnetism is defined as the integral of their dot product over three-dimensional space. If F is a harmonic mode, it can be normalized such that (F, F) equals one by expressing F as a scalar multiple of another vector field F'. This normalization simplifies verification of the inner product being equal to one. The discussion clarifies that substituting the normalized form into the inner product confirms the result without needing to worry about the dot product being zero. The process illustrates the flexibility in handling solutions within electromagnetic systems.
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I'm reading a textbook on electromagnetism. It says that for two vector fields ##\textbf{F}(\textbf{r})##
and ##\textbf{G}(\textbf{r})## their inner product is defined as

##(\textbf{F},\textbf{G}) = \int \textbf{F}^{*}\cdot \textbf{G} \thinspace d^3\textbf{r}##

And that if ##\textbf{F}## is a harmonic mode of an electromagnetic system we can always set ##(\textbf{F},\textbf{F})=1##. To demonstrate this they set
##\textbf{F} = \frac{\textbf{F}'}{\sqrt{(\textbf{F}',\textbf{F}')}}##
Then say this is a scalar multiple of ##\textbf{F}##, so it's really the same solution (which is because you can add two solutions, multiplied by a constant, together to get another solution). Setting ##\textbf{F}## to have this value allows the reader to easily verify that we can always set this inner product to be one. How does it let me easily verify that? That dot product has to be zero for the inner product to be 1, doesn't it?
 
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Just substituting in works fine, sorry! Made a mistake!
 
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