Spherical layer charge distribution and multipole expansion

[Horacius.Rex]

Hi,

I have a random spherical distribution of N charges between radiuses
R1 and R2. N is up to 10^9 or more.I want to calculate the
electrostatic potential closed to the origin of the sphere. R1 and R2
are much bigger than the distance of this point to the origin. So I
thought about using the multipole expansion to calculate the
potential, because it is supposed to reduce the Tcpu a lot, mainly
because in this approach Tcpu proportional to N, and in explicit
electrostatical potential calculation Tcpu proportional to N^2. So,
could you recommendme references in good books or papers or weblinks
with examples of similar calculations ?

Thanks

 

[lityk]

check http://www.fastmultipole.org/

Start with tutorial