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arXiv · 2510.15998

AMStraMGRAM: Adaptive Multi-cutoff Strategy Modification for ANaGRAM

Nilo Schwencke·Cyriaque Rousselot·Alena Shilova·Cyril Furtlehner
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Abstract

Recent works have shown that natural gradient methods can significantly outperform standard optimizers when training physics-informed neural networks (PINNs). In this paper, we analyze the training dynamics of PINNs optimized with ANaGRAM, a natural-gradient-inspired approach employing singular value decomposition with cutoff regularization. Building on this analysis, we propose a multi-cutoff adaptation strategy that further enhances ANaGRAM's performance. Experiments on benchmark PDEs validate the effectiveness of our method, which allows to reach machine precision on some experiments. To provide theoretical grounding, we develop a framework based on spectral theory that explains the necessity of regularization and extend previous shown connections with Green's functions theory.

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Nilo Schwencke, Cyriaque Rousselot, Alena Shilova, Cyril Furtlehner. 2025-10-14. AMStraMGRAM: Adaptive Multi-cutoff Strategy Modification for ANaGRAM. https://arxiv.org/abs/2510.15998

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