activity
20242026
collaborators

10 papers

math.NA2026

Adaptive singularity swap quadrature for near-singular layer potentials on axisymmetric surfaces

David Krantz, Anna-Karin Tornberg

When numerically evaluating layer potentials at target points close to the domain boundary, specialized quadrature techniques are required for accuracy because of rapid variations…

math.NA2026

Fast unified evaluation of layer and volume potentials for the 2D modified Helmholtz equation

Edith Frisk Gärtner, Fredrik Fryklund, Anna-Karin Tornberg

We present a fast and accurate potential theory-based method for the two-dimensional modified Helmholtz equation, treating the involved singular and nearly singular layer evaluatio…

math.NA2026

Fast summation on rectangular cuboids with arbitrary periodicity in the DMK framework

David Krantz, Ludvig af Klinteberg, Anna-Karin Tornberg

Dual-space multilevel kernel-splitting (DMK) is a fast summation framework that combines ideas from the fast multipole method, Ewald summation, and multilevel summation. Originally…

math.NA2026

Preconditioning for near-contacts in large 2D Stokes flows: a locally compressed method of fundamental solutions

Anna Broms, Anna-Karin Tornberg, Alex H. Barnett

We tackle two key difficulties in the simulation of the viscous hydrodynamics of a large dense collection of rigid particles: (i) the poor convergence rate of an iterative solution…

math.NA2026

Stabilizing the singularity swap quadrature for near-singular line integrals

David Krantz, Alex H. Barnett, Anna-Karin Tornberg

Singularity swap quadrature (SSQ) is an effective method for the evaluation at nearby targets of potentials due to densities on curves in three dimensions. While highly accurate in…

math.NA2026

Fast Ewald Summation using Prolate Spheroidal Wave Functions

Erik Boström, Anna-Karin Tornberg, Ludvig af Klinteberg

Fast Ewald summation efficiently evaluates Coulomb interactions and is widely used in molecular dynamics simulations. It is based on a split into a short-range and a long-range par…