Multifidelity domain decomposition-based physics-informed neural networks and operators for time-dependent problems
Alexander Heinlein, Amanda A. Howard, Damien Beecroft, Panos Stinis
TL;DR
This work tackles multiscale time-dependent PDEs by addressing PINN limitations from spectral bias through a novel combination of multifidelity stacking PINNs and domain-decomposition-based finite-basis PINNs (FBPINNs). The method introduces time-domain decomposition with hierarchical, multifidelity networks (stacking FBPINNs) to learn high-frequency multiscale features more efficiently, achieving superior accuracy on challenging tests such as a pendulum, a two-frequency model, and the Allen-Cahn equation. It also extends to operator learning via multifidelity stacking DeepONets (FB-DONs), enabling rapid surrogate solutions for varying initial conditions. The framework demonstrates improved accuracy and efficiency over traditional PINNs and prior stacking approaches, with detailed training parameters and clear potential as surrogate solvers and multi-physics integrations across scales.
Abstract
Multiscale problems are challenging for neural network-based discretizations of differential equations, such as physics-informed neural networks (PINNs). This can be (partly) attributed to the so-called spectral bias of neural networks. To improve the performance of PINNs for time-dependent problems, a combination of multifidelity stacking PINNs and domain decomposition-based finite basis PINNs is employed. In particular, to learn the high-fidelity part of the multifidelity model, a domain decomposition in time is employed. The performance is investigated for a pendulum and a two-frequency problem as well as the Allen-Cahn equation. It can be observed that the domain decomposition approach clearly improves the PINN and stacking PINN approaches. Finally, it is demonstrated that the FBPINN approach can be extended to multifidelity physics-informed deep operator networks.
