We develop a novel computational framework to approximate solution operators of evolution partial differential equations (PDEs). By employing a general nonlinear reduced-order model, such as a deep neural network, to approximate the solution of a given PDE, we realize that the evolution of the model parameter is a control problem in the parameter space. Based on this observation, we propose to approximate the solution operator of the PDE by learning the control vector field in the parameter space. From any initial value, this control field can steer the parameter to generate a trajectory such that the corresponding reduced-order model solves the PDE. This allows for substantially reduced computational cost to solve the evolution PDE with arbitrary initial conditions. We also develop comprehensive error analysis for the proposed method when solving a large class of semilinear parabolic PDEs. Numerical experiments on different high-dimensional evolution PDEs with various initial conditions demonstrate the promising results of the proposed method.
翻译:我们开发了一个新的计算框架,以接近进化部分差异方程式(PDEs)的解决方案操作员。我们通过使用一般的非线性减序模型,例如深神经网络,以近似给定的PDE的解决方案,我们认识到模型参数的演变是参数空间的一个控制问题。根据这一观察,我们提议通过在参数空间学习控制矢量场来接近PDE的解决方案操作员。从任何初始值中,这个控制字段都可以引导参数产生一个轨迹,使相应的减序模型解决PDE。这样可以大幅降低计算成本,以任意的初始条件解决进化PDE。我们还在解决大型半线性半线性参数 PDEs时对拟议方法进行了全面的错误分析。不同高度进化 PDEs 的数值实验及其各种初始条件显示了拟议方法的有希望的结果。