Half of the GRAND CHALLENGE EQUATIONS (courtesy of San Diego Supercomputer Center) 

1.  ¶_{t}v + (v×Ñ)v =  (1/r)ÑP + Ñ^{2} v  ÑF  A.  Poisson Equation  
2.  Ñ^{2}u = ¶_{t}u  B.  Discrete Fourier Transform  
3.   Ñ^{2} u + lu = f  C.  Helmholtz Equation  
4.  [ ¶_{x} ¶_{x} F + ¶_{y} ¶_{y} F + ¶_{z} ¶_{z} F ] = 4p Gr  D.  Schroedinger Equation  
5. 

E.  NavierStokes Equation  
6.   [ h / ( 2pi ) ] ¶_{t}Y(r,t) =  [ h^{2} / ( 8p^{2}m ) ] Ñ^{2} Y(r,t) + VY(r,t)  F.  Heat Equation 