Also, how can N bodies orbit each other? Don't they know there is no analytic solution to their problem? Sheesh! (Maybe they are using floating-point?)

I'm not totally familiar with the Navier-Stokes equations, but from what I've just read (please correct me if I'm wrong!), I think the difficulty of the Navier-Stokes equation is reasoning about the solution set, while with quantum constructions the issue is whether or not a solution exists for some specific macroscopic system.

I agree

For those who never saw the Navier-Stokes equation: http://en.wikipedia.org/wiki/Navier_Stokes#Derivation_and_de...

That's it. It looks simple but it involves Tensor math.