Bayesian bilevel operator learning with low-rank adaptation for efficient uncertainty quantification of PDE inverse problems.
5 affiliations
- 1Department of Mathematical Sciences, Worcester Polytechnic Institute, Worcester, MA, USA. [email protected].
- 2Department of Mathematics, University of California, Irvine, Irvine, CA, USA.
- 3Department of Computer Science, University of California, Irvine, Irvine, CA, USA.
- 4Department of Mathematics, University of California, Irvine, Irvine, CA, USA. [email protected].
- 5Department of Biomedical Engineering, University of California, Irvine, Irvine, CA, USA. [email protected].
Abstract
Uncertainty quantification in PDE inverse problems is essential in many applications. Scientific machine learning and AI enable data-driven learning of model components while preserving physical structure, and provide the scalability and adaptability needed for emerging imaging technologies and clinical insights. We develop a Bilevel Local Operator Learning framework for Bayesian inference in PDEs (B-BiLO). At the upper level, we sample parameters from the posterior via Hamiltonian Monte Carlo, while at the lower level we fine-tune a neural network via low-rank adaptation (LoRA) to approximate the solution operator locally. B-BiLO enables efficient gradient-based sampling without synthetic data or adjoint equations and avoids sampling in high-dimensional weight space, as in Bayesian neural networks, by optimizing weights deterministically. We analyze errors from approximate lower-level optimization and establish their impact on posterior accuracy. Numerical experiments across PDE models, including tumor growth, demonstrate that B-BiLO achieves accurate and efficient uncertainty quantification.
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BibTeX
@article{zhang2026bayesian,
title = {{Bayesian bilevel operator learning with low-rank adaptation for efficient uncertainty quantification of PDE inverse problems.}},
author = {Ray Zirui Zhang and Christopher E Miles and Xiaohui Xie and John S Lowengrub},
journal = {Nature communications},
year = {2026},
month = sep,
doi = {10.1038/s41467-026-77768-7},
url = {https://europepmc.org/article/MED/42901898},
note = {CC BY},
}
RIS
TY - JOUR
TI - Bayesian bilevel operator learning with low-rank adaptation for efficient uncertainty quantification of PDE inverse problems.
AU - Ray Zirui Zhang
AU - Christopher E Miles
AU - Xiaohui Xie
AU - John S Lowengrub
PY - 2026
DA - 2026/09/19
JO - Nature communications
DO - 10.1038/s41467-026-77768-7
UR - https://europepmc.org/article/MED/42901898
AB - Uncertainty quantification in PDE inverse problems is essential in many applications. Scientific machine learning and AI enable data-driven learning of model components while preserving physical structure, and provide the scalability and adaptability needed for emerging imaging technologies and clinical insights. We develop a Bilevel Local Operator Learning framework for Bayesian inference in PDEs (B-BiLO). At the upper level, we sample parameters from the posterior via Hamiltonian Monte Carlo, while at the lower level we fine-tune a neural network via low-rank adaptation (LoRA) to approximate the solution operator locally. B-BiLO enables efficient gradient-based sampling without synthetic data or adjoint equations and avoids sampling in high-dimensional weight space, as in Bayesian neural networks, by optimizing weights deterministically. We analyze errors from approximate lower-level optimization and establish their impact on posterior accuracy. Numerical experiments across PDE models, including tumor growth, demonstrate that B-BiLO achieves accurate and efficient uncertainty quantification.
SN - 2041-1723
ER -