🚀 go-pugleaf

I wondered if there are any methods solving the following partial 
differential equation in asymptotic limit. I am interested in the 
behavior of h(x,y,t) as TIME IS LARGE 

\partial_{t} h(x,y,t)= -L^{2}[h(x,y,t)] - L[h(x,y,t)] 
                       -|G[h(x,y,t)]|^{2}

where L is the laplacian operator i.e. \partial^{2}_{x} +\partial^{2}_{y}
      L^{2}= L . L
      G is the gradient operator

(the equation reduces to 1st order couple o.d.e  in fourie space. However 
 the system size i am interested is  at least 2000 X 2000) 


--khl