Statistical moments and multipole moments

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In statistics, moments of a distribution can be derived using generating functions, specifically through the relation involving the exponential function and its derivatives. The discussion raises the question of whether a similar generating function approach exists for deriving multipole moments in electrodynamics. Multipole moments are linked to the expansion of the potential function 1/|x|, which represents the electric field at a point. However, a clear connection to a generating function for multipole moments is not established in the conversation. Further research or insights from others in the forum may be needed to clarify this relationship.
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Hello,

in statistics, one can derive the moments of a distribution by using a generating function
<x^n> = \int dx x^n f(x) = \left( \frac {d}{dt} \int dx \exp(tx) f(x) \right)_{t=0} = \left( \frac d {dt} M(t) \right)_{t=0}

Is there a similar method to derive the multipole moments in electrodynamics, e.g. is there a generating function? I know that the multipole moments are derived from the expansion of
\frac {1}{\left|x\right|}
but I don't seem to get the connection to a generating function.
 
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Hi there,

I'm not sure if there is a similar method to deriving the multipole moments in electrodynamics using a generating function as with statistics. I think the multipole moments are derived from the expansion of \frac {1}{\left|x\right|} because this is a measure of the electric field at a given point, which is related to the multipole moments. Have you tried researching this further? Maybe someone else on the forum may have more information on this topic that can help provide more insight.
 
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