In the public owned domain are several spendy supercomputers that
could easily perform such complex 3D interactive simulations as based
entirely on the known laws of physics. For some reason, those are all
off-limits to outsiders like yourself.

It does not really matter that I do not have access to a large super
computer, or operate a botnet ;-)
The probect should only demonstrate to acertain degree the phenomena I am
considering. It is not supposed to break new grounds in astrophysics, so
offline calculation of less than 100k particles will do fine for my purpose.