In this article, we introduce a novel parallel-in-time solver for nonlinear ordinary differential equations (ODEs). We state the numerical solution of an ODE as a root-finding problem that we solve using Newton's method. The affine recursive operations arising in Newton's step are parallelized in time by using parallel prefix sums, that is, parallel scan operations, which leads to a logarithmic span complexity. This yields an improved runtime compared to the previously proposed Parareal method. We demonstrate the computational advantage through numerical simulations of various systems of ODEs.
翻译:本文提出了一种用于非线性常微分方程(ODEs)的新型并行时间求解器。我们将ODE的数值解表述为根求解问题,并采用牛顿法进行求解。牛顿迭代步骤中产生的仿射递归运算通过并行前缀和(即并行扫描操作)在时间维度上实现并行化,从而获得对数跨度复杂度。与先前提出的Parareal方法相比,该方法显著提升了运行效率。我们通过对多种ODE系统的数值模拟验证了其计算优势。