We consider solutions of the Poisson equation on a family of domains with
holes shrinking to a point. Assuming Robin or Neumann boundary conditions on
the boundary of the holes we show that the solution converges uniformly to
the solution of the Poisson equation on the domain without the holes.
This is in contrast to Dirichlet boundary conditions where there is no
uniform convergence. The results substantially improve earlier results on
This is joint work with E.N. Dancer and Daniel Hauer.