Wavelets for the Fast Solution of Second-Kind Integral Equations

Abstract : A class of vector-space bases is introduced for the sparse representation of discretizations of integral operators. An operator with a smooth, non-oscillatory kernel possessing a finite number of singularities in each row or column is represented in these bases as a sparse matrix, to high precision. A method is presented that employs these bases for the numerical solution of second-kind integral equations in time bounded by O(nlog squared n) , where n is the number of points in the discretization. Numerical results are given which demonstrate the effectiveness of the approach, and several generalizations and applications of the method are discussed.