Boundary Integral Operators in Countably Normed Spaces

Norbert Heuer, Ernst P. Stephan
Math. Nachr., 191 (1), 123-151, 1998.

Abstract
We show the mapping properties of several integral operators acting on polygons within countably normed spaces. The integral operators are the weakly singular single layer potential operator for the Laplacian, the corresponding double layer potential operator and the normal derivatives of these operators. Our analysis of the boundary integral equations in the countably normed spaces is based on Mellin techniques and uses the Mellin symbols of the integral operators. Functions of these countably normed spaces can be approximated very efficiently by splines through the use of well adapted mesh-refinement and polynomial degree distribution. Therefore the hp-version of the boundary element method with geometric mesh can be proved to converge exponentially fast for the solutions to those integral equations.