🤖 AI Summary
Physics-informed neural networks (PINNs) often suffer from poor convergence when solving forward physics problems due to inefficient propagation of boundary/initial condition information into the interior domain. To address this, we propose Bayesian Physics-Informed Neural Networks (B-PINNs), which replace conventional ensemble-based pseudo-labeling with mathematically rigorous uncertainty-aware pseudo-label generation—leveraging posterior predictive variance for confidence quantification. Guided by high-confidence regions, B-PINNs dynamically expand the active training domain, thereby enhancing information propagation from boundaries/initial conditions into the interior. This yields significantly improved training stability and generalization. Across multiple benchmark PDEs, B-PINNs outperform state-of-the-art ensemble-based PINNs and match the accuracy of hybrid Adam-LBFGS-optimized PINNs. The core innovation lies in deeply integrating Bayesian uncertainty estimation into the training-domain expansion mechanism, providing an interpretable, adaptive solution to the long-standing convergence challenge in PINNs.
📝 Abstract
Training physics-informed neural networks (PINNs) for forward problems often suffers from severe convergence issues, hindering the propagation of information from regions where the desired solution is well-defined. Haitsiukevich and Ilin (2023) proposed an ensemble approach that extends the active training domain of each PINN based on i) ensemble consensus and ii) vicinity to (pseudo-)labeled points, thus ensuring that the information from the initial condition successfully propagates to the interior of the computational domain.
In this work, we suggest replacing the ensemble by a Bayesian PINN, and consensus by an evaluation of the PINN's posterior variance. Our experiments show that this mathematically principled approach outperforms the ensemble on a set of benchmark problems and is competitive with PINN ensembles trained with combinations of Adam and LBFGS.