Title:       Overcoming corner singularities by multigrid methods

Author:      Susanne C. Brenner

Published:   SIAM Journal of Numerical Analysis
             v. 35 (1998),  1883-1892 (MR# 99f:65189)

Abstract: We consider the Poisson equation $-\Delta u = f$ with 
the homogeneous Dirichlet boundary condition on a two-dimensional 
polygonal domain $\O$.  We develop a finite element multigrid method
on quasi-uniform grids that has an order of convergence  
${\Cal{O}}(h^{m+1-\epsilon})$ in the $H^1(\O)$ norm for any 
positive $\epsilon$ when $f \in H^m(\O)$. The cost of the method 
is proportional to the number of elements in the triangulation.    
The results of this paper can be generalized to other equations 
and other boundary conditions.

* paper: SIAM Journal on Numerical Analysis
Presented at: -Approximation and PDEs, Foundations of Computational Mathematics, Rio de Janeiro, Brazil, January 5--12, 1997 -Eighth Copper Mountain Conference on Multigrid Methods, Copper Mountain, Colorado, April 6--11, 1997 -Third IMACS International Symposium on Iterative Methods in Scientific Computation, Jackson Hole, WY, July 9--12, 1997 -Guangzhou International Symposium on Computational Mathematics, Guangzhou, PRC, August 11-15, 1997 -Innovative Finite Element Computations in Continuum Mechanics, 15th IMACS World Congress, Berlin, Germany, August 24--29, 1997 -Imperial College, University of London, July 14, 1998 -University of Leeds, July 16, 1998 -University of Loughborough, July 17, 1998