🧮 Scientific Computing¶
🧠 NeurIPS2025 · 24 paper notes
- A Regularized Newton Method for Nonconvex Optimization with Global and Local Complexity Guarantees
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This paper proposes a novel class of regularizers constructed from current and historical gradients, combined with a conjugate gradient method equipped with negative-curvature detection to solve the regularized Newton equation. Within an adaptive framework that requires no prior knowledge of the Hessian Lipschitz constant, the method simultaneously achieves, for the first time, the optimal global iteration complexity of \(O(\epsilon^{-3/2})\) and a quadratic local convergence rate.
- Bayesian Surrogates for Risk-Aware Pre-Assessment of Aging Bridge Portfolios
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A Bayesian neural network (BNN)-based surrogate model is proposed to replace expensive nonlinear finite element analysis (NLFEA), enabling rapid, uncertainty-aware structural safety pre-assessment of aging bridge portfolios. In a real-world railway case study, the approach saves approximately $370,000 per bridge.
- Collapsing Taylor Mode Automatic Differentiation
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This paper proposes a collapsing optimization technique for Taylor mode automatic differentiation. By rewriting the computation graph to propagate derivative summation operations upward, it substantially accelerates the evaluation of PDE operators (e.g., Laplacian, general linear PDE operators), achieving speeds superior to nested backpropagation while retaining the low-memory advantage of forward-mode AD.
- DeltaPhi: Physical States Residual Learning for Neural Operators in Data-Limited PDE Solving
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This paper proposes DeltaPhi, a framework that forgoes direct learning of the input-to-output mapping for PDEs and instead learns residuals between similar physical states. By exploiting the stability of physical systems as implicit data augmentation, DeltaPhi significantly improves the performance of diverse neural operators under data-scarce regimes.
- EddyFormer: Accelerated Neural Simulations of Three-Dimensional Turbulence at Scale
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EddyFormer is a Transformer architecture based on the Spectral Element Method (SEM) that decomposes the flow field into two parallel streams — LES (large-scale) and SGS (small-scale) — achieving DNS-level accuracy on 3D turbulence at \(256^3\) resolution with a 30× speedup, while generalizing well to unseen domains 4× larger.
- Enforcing Governing Equation Constraints in Neural PDE Solvers via Training-free Projections
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Two training-free post-processing projection methods are proposed—nonlinear LBFGS optimization and local linearization projection—to project the outputs of neural PDE solvers onto the feasible manifold satisfying governing equation constraints. Evaluated on Lorenz/KS/Navier-Stokes, both methods substantially reduce constraint violations and improve accuracy, markedly outperforming physics-informed training.
- F-Adapter: Frequency-Adaptive Parameter-Efficient Fine-Tuning in Scientific Machine Learning
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This paper presents the first systematic study of parameter-efficient fine-tuning (PEFT) for pretrained large operator models (LOMs) in scientific machine learning. It demonstrates that LoRA exhibits a depth-amplified approximation error lower bound in Fourier layers, whereas Adapter preserves universal approximation capacity. Building on this analysis, the paper proposes the Frequency-Adaptive Adapter (F-Adapter), which allocates adapter capacity according to spectral energy distribution. On 3D Navier-Stokes prediction tasks, F-Adapter achieves state-of-the-art performance while tuning fewer than 2% of parameters.
- From Black Hole to Galaxy: Neural Operator Framework for Accretion and Feedback Dynamics
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A Neural Operator-based "sub-grid black hole" model is proposed to learn the small-scale (GR)MHD time-evolution operator \(u_t \to u_{t+\Delta T}\), replacing hand-crafted closure rules embedded in a multi-level direct numerical simulation framework. This work achieves, for the first time, the capture of intrinsic variability in accretion-driven feedback, with a speedup of \(\sim 10^5\times\).
- From Images to Physics: Probabilistic Inference of Galaxy Parameters and Emission Lines via VAE & Normalizing Flows
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This work proposes a VAE–Normalizing Flow hybrid framework that jointly infers galaxy physical parameters (stellar mass, SFR, redshift, gas-phase metallicity, central black hole mass) and emission line fluxes (Hα, Hβ, [N II], [O III]) in a probabilistic manner from SDSS gri images and photometric data, achieving over 100× speedup relative to SED fitting while providing well-calibrated posterior distributions.
- GyroSwin: 5D Surrogates for Gyrokinetic Plasma Turbulence Simulations
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This work presents GyroSwin, the first scalable 5D neural surrogate model for gyrokinetic plasma turbulence. It extends the Swin Transformer to the 5D gyrokinetic phase space, employs cross-attention for 3D↔5D interaction, and adopts channelwise mode separation to capture zonal flows. GyroSwin achieves higher accuracy than conventional quasilinear methods while being three orders of magnitude faster than the numerical solver GKW.
- Hamiltonian Neural PDE Solvers through Functional Approximation
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Grounded in the Riesz representation theorem, this work approximates infinite-dimensional Hamiltonian functionals via learnable integral kernel functionals (IKF). Functional derivatives are obtained through automatic differentiation, yielding an energy-conserving neural PDE solver (HNS) that demonstrates superior stability and generalization on 1D/2D PDEs.
- INC: An Indirect Neural Corrector for Auto-Regressive Hybrid PDE Solvers
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This paper proposes the Indirect Neural Corrector (INC), which embeds learned correction terms into the right-hand side (RHS) of PDEs rather than directly modifying the state. The approach is theoretically shown to reduce error amplification by a factor of \(\mathcal{O}(\Delta t^{-1}+L)\), and achieves substantial improvements in long-term trajectory performance across 6 PDE systems (from 1D chaos to 3D turbulence), with R² gains up to 158.7% and up to 330× acceleration.
- Integration Matters for Learning PDEs with Backward SDEs
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This paper identifies the root cause of why standard BSDE methods underperform PINNs — an irreducible discretization bias introduced by Euler-Maruyama integration — and proposes Heun-BSDE based on the Stratonovich formulation to fully eliminate this bias, achieving competitive performance against PINNs on high-dimensional PDEs.
- Multi-Trajectory Physics-Informed Neural Networks for HJB Equations with Hard-Zero Terminal Inventory: Optimal Execution on Synthetic & SPY Data
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To address the hard-zero terminal inventory constraint (\(X_T=0\)) in HJB equations arising from optimal trade execution, this paper proposes Multi-Trajectory PINN (MT-PINN). Through a rollout-based terminal loss and a \(\lambda\)-curriculum training strategy, MT-PINN significantly outperforms vanilla PINN on both synthetic benchmarks and live SPY backtesting, achieving a substantial reduction in terminal inventory violation rates.
- Neural Emulator Superiority: When Machine Learning for PDEs Surpasses its Training Data
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This work challenges the prevailing assumption that the accuracy of neural PDE emulators is bounded by that of their training data (i.e., the numerical solver). It discovers and rigorously defines the phenomenon of emulator superiority—neural networks trained solely on low-accuracy solver data can, when evaluated against high-accuracy reference solutions, outperform the very solver that generated their training data.
- Neuro-Spectral Architectures for Causal Physics-Informed Networks
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NeuSA integrates classical spectral methods with Neural ODEs: the PDE is projected onto a spectral basis (Fourier) to obtain an ODE system, which is then solved by a NODE that learns the dynamical evolution. This architecture-level design eliminates the spectral bias and causality violations inherent in conventional PINNs, achieving errors 1–2 orders of magnitude lower than baselines on wave, Burgers, and sine-Gordon equations while training faster.
- From Images to Physics: Probabilistic Inference of Galaxy Parameters and Emission Lines via VAE–Normalizing Flows
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A two-stage VAE–Normalizing Flow probabilistic inference framework is proposed that infers stellar mass, SFR, redshift, black hole mass, metallicity, and emission line fluxes directly from SDSS galaxy images and photometric data, surpassing existing non-spectroscopic methods in accuracy while being over 100× faster than SED fitting.
- One-Shot Transfer Learning for Nonlinear PDEs with Perturbative PINNs
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By combining perturbation theory with PINNs, this work decomposes nonlinear PDEs into a sequence of linear subproblems. After learning the latent space of the linear operator via a Multi-Head PINN, transfer to new PDE instances is achieved through a closed-form solution within 0.2 seconds, attaining errors on the order of \(10^{-3}\).
- Physics-Guided Machine Learning for Uncertainty Quantification in Turbulence Models
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This paper proposes a hybrid ML–EPM framework that employs a lightweight CNN to learn a correction mapping from RANS turbulent kinetic energy fields to DNS ground truth, using the learned corrections to modulate the perturbation magnitude of the Eigenspace Perturbation Method (EPM). The approach reduces uncertainty estimation errors by 1–2 orders of magnitude while preserving physical consistency.
- Physics-Informed Neural Networks with Fourier Features and Attention-Driven Decoding
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This paper proposes Spectral PINNsformer (S-Pformer), which replaces the encoder of PINNsformer with Fourier feature embeddings and adopts a decoder-only Transformer architecture. S-Pformer achieves superior performance on multiple PDE benchmarks while reducing parameter count by 18.6%, effectively alleviating the spectral bias problem.
- Stable Minima of ReLU Neural Networks Suffer from the Curse of Dimensionality: The Neural Shattering Phenomenon
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This paper investigates the generalization properties of stable minima (flat minima) in two-layer overparameterized ReLU networks. It proves that while flatness does imply generalization, the convergence rate deteriorates exponentially with input dimension (i.e., the curse of dimensionality applies), forming an exponential separation from low-norm solutions (weight decay) that are immune to this curse. The paper further identifies the "neural shattering" phenomenon as the geometric mechanism underlying failure in high dimensions.
- Symbolic Regression Is All You Need: From Simulations to Scaling Laws in Binary Neutron Star Mergers
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This work applies Symbolic Regression (SR) to automatically discover analytic calibration relations for post-merger accretion disk mass in binary neutron star mergers from numerical relativity simulation data. The resulting compact expressions comprehensively outperform existing empirical fitting formulae in the literature in terms of predictive accuracy, generalization, and interpretability.
- The Primacy of Magnitude in Low-Rank Adaptation
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This paper reveals that weight update magnitude is the fundamental driver of performance in LoRA, unifying the influence of learning rate, scaling factor, and initialization strategy under a single framework. It further proposes LoRAM—an efficient initialization method based on deterministic orthogonal bases and magnitude scaling—that matches or surpasses spectral initialization methods without requiring SVD.
- Towards Universal Neural Operators through Multiphysics Pretraining
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This paper proposes an adapter-based multiphysics pretraining framework for neural operators. By treating lifting/projection layers as problem-specific adapters and freezing shared kernel integration operator layers, the framework enables transfer learning across PDE problems, substantially reducing fine-tuning cost while improving generalization.