Acceleration of the space-time boundary element method using GPUs

Matrices arising from the space-time boundary element method for the heat equation are dense and are global in space and time. Thus, they require a large amount of memory which may pose a problem when accelerating the code using GPUs. In this paper, we present a method that overcomes this issue by assembling elements of system matrices only when needed during matrix-vector multiplication. Although this requires a significantly larger amount of floating-point operations when the matrix is repeatedly applied, due to the large processing power of modern GPUs, we are still able to achieve a significant speedup compared to the original CPU code.