Lazy Diffusion: Mitigating spectral collapse in generative diffusion-based stable autoregressive emulation of turbulent flows
- URL: http://arxiv.org/abs/2512.09572v1
- Date: Wed, 10 Dec 2025 12:05:32 GMT
- Title: Lazy Diffusion: Mitigating spectral collapse in generative diffusion-based stable autoregressive emulation of turbulent flows
- Authors: Anish Sambamurthy, Ashesh Chattopadhyay,
- Abstract summary: We show that standard DDPMs induce a fundamental emphspectral collapse.<n>We introduce power-law schedules that preserve fine-scale structure deeper into diffusion time.<n>These methods are applied to high-Reynolds-number 2D Kolmogorov turbulence and $1/12circ$ Gulf of Mexico ocean reanalysis.
- Score: 0.0
- License: http://creativecommons.org/licenses/by/4.0/
- Abstract: Turbulent flows posses broadband, power-law spectra in which multiscale interactions couple high-wavenumber fluctuations to large-scale dynamics. Although diffusion-based generative models offer a principled probabilistic forecasting framework, we show that standard DDPMs induce a fundamental \emph{spectral collapse}: a Fourier-space analysis of the forward SDE reveals a closed-form, mode-wise signal-to-noise ratio (SNR) that decays monotonically in wavenumber, $|k|$ for spectra $S(k)\!\propto\!|k|^{-λ}$, rendering high-wavenumber modes indistinguishable from noise and producing an intrinsic spectral bias. We reinterpret the noise schedule as a spectral regularizer and introduce power-law schedules $β(τ)\!\propto\!τ^γ$ that preserve fine-scale structure deeper into diffusion time, along with \emph{Lazy Diffusion}, a one-step distillation method that leverages the learned score geometry to bypass long reverse-time trajectories and prevent high-$k$ degradation. Applied to high-Reynolds-number 2D Kolmogorov turbulence and $1/12^\circ$ Gulf of Mexico ocean reanalysis, these methods resolve spectral collapse, stabilize long-horizon autoregression, and restore physically realistic inertial-range scaling. Together, they show that naïve Gaussian scheduling is structurally incompatible with power-law physics and that physics-aware diffusion processes can yield accurate, efficient, and fully probabilistic surrogates for multiscale dynamical systems.
Related papers
- Adaptive Spectral Feature Forecasting for Diffusion Sampling Acceleration [58.19554276924402]
We propose spectral diffusion feature forecaster (Spectrum) to enable global, long-range feature reuse with tightly controlled error.<n>We achieve up to 4.79$times$ speedup on FLUX.1 and 4.67$times$ speedup on Wan2.1-14B, while maintaining much higher sample quality compared with the baselines.
arXiv Detail & Related papers (2026-03-02T08:59:11Z) - Parallel Complex Diffusion for Scalable Time Series Generation [50.01609741902786]
PaCoDi is a spectral-native architecture that decouples generative modeling in the frequency domain.<n>We show that PaCoDi outperforms existing baselines in both generation quality and inference speed.
arXiv Detail & Related papers (2026-02-10T14:31:53Z) - Spectral Gating Networks [65.9496901693099]
We introduce Spectral Gating Networks (SGN) to introduce frequency-rich expressivity in feed-forward networks.<n>SGN augments a standard activation pathway with a compact spectral pathway and learnable gates that allow the model to start from a stable base behavior.<n>It consistently improves accuracy-efficiency trade-offs under comparable computational budgets.
arXiv Detail & Related papers (2026-02-07T20:00:49Z) - Dynamical Regimes of Multimodal Diffusion Models [0.0]
We present a theoretical framework for coupled diffusion models, using coupled Ornstein-Uhlenbeck processes as a tractable model.<n>A key prediction is the synchronization gap'', a temporal window during the reverse generative process where distinct eigenmodes stabilize at different rates.<n>We show that the coupling strength acts as a spectral filter that enforces a tunable temporal hierarchy on generation.
arXiv Detail & Related papers (2026-02-04T17:16:12Z) - Latent Object Permanence: Topological Phase Transitions, Free-Energy Principles, and Renormalization Group Flows in Deep Transformer Manifolds [0.5729426778193398]
We study the emergence of multi-step reasoning in deep Transformer language models through a geometric and statistical-physics lens.<n>We formalize the forward pass as a discrete coarse-graining map and relate the appearance of stable "concept basins" to fixed points of this renormalization-like dynamics.<n>The resulting low-entropy regime is characterized by a spectral tail collapse and by the formation of transient, reusable object-like structures in representation space.
arXiv Detail & Related papers (2026-01-16T23:11:02Z) - An Inverse Scattering Inspired Fourier Neural Operator for Time-Dependent PDE Learning [0.0]
We introduce an inverse scattering inspired Fourier Neural Operator (IS-FNO)<n>IS-FNO achieves lower short-term errors and substantially improved long-horizon stability in non-stiff regimes.<n>Overall, this work shows that incorporating physical structure -- particularly reversibility and spectral evolution -- into neural operator design significantly enhances robustness and long-term predictive fidelity for nonlinear PDE dynamics.
arXiv Detail & Related papers (2025-12-22T14:40:13Z) - Resolving Turbulent Magnetohydrodynamics: A Hybrid Operator-Diffusion Framework [0.1572025118388268]
Hybrid machine learning framework is trained on a comprehensive ensemble of high-fidelity simulations with $mathrmRe in 100, 250, 500, 750, 1000, 3000, 10000$.<n>At extreme turbulence levels, it remains the first surrogate capable of recovering the high-wavenumber evolution of the magnetic field.
arXiv Detail & Related papers (2025-07-02T19:33:57Z) - Elucidated Rolling Diffusion Models for Probabilistic Weather Forecasting [52.6508222408558]
We introduce Elucidated Rolling Diffusion Models (ERDM)<n>ERDM is the first framework to unify a rolling forecast structure with the principled, performant design of Elucidated Diffusion Models (EDM)<n>On 2D Navier-Stokes simulations and ERA5 global weather forecasting at 1.5circ resolution, ERDM consistently outperforms key diffusion-based baselines.
arXiv Detail & Related papers (2025-06-24T21:44:31Z) - Turb-L1: Achieving Long-term Turbulence Tracing By Tackling Spectral Bias [43.0262112921538]
We propose Turb-L1, an innovative turbulence prediction method.<n>It accurately captures cross-scale interactions and preserves the fidelity of high-frequency dynamics.<n>In long-term predictions, it reduces Mean Squared Error (MSE) by $80.3%$ and increases Structural Similarity (SSIM) by over $9times$ compared to the SOTA baseline.
arXiv Detail & Related papers (2025-05-25T08:38:55Z) - FLEX: A Backbone for Diffusion-Based Modeling of Spatio-temporal Physical Systems [51.15230303652732]
FLEX (F Low EXpert) is a backbone architecture for generative modeling of-temporal physical systems.<n>It reduces the variance of the velocity field in the diffusion model, which helps stabilize training.<n>It achieves accurate predictions for super-resolution and forecasting tasks using as few features as two reverse diffusion steps.
arXiv Detail & Related papers (2025-05-23T00:07:59Z) - Generative Fractional Diffusion Models [53.36835573822926]
We introduce the first continuous-time score-based generative model that leverages fractional diffusion processes for its underlying dynamics.
Our evaluations on real image datasets demonstrate that GFDM achieves greater pixel-wise diversity and enhanced image quality, as indicated by a lower FID.
arXiv Detail & Related papers (2023-10-26T17:53:24Z) - Convergence of mean-field Langevin dynamics: Time and space
discretization, stochastic gradient, and variance reduction [49.66486092259376]
The mean-field Langevin dynamics (MFLD) is a nonlinear generalization of the Langevin dynamics that incorporates a distribution-dependent drift.
Recent works have shown that MFLD globally minimizes an entropy-regularized convex functional in the space of measures.
We provide a framework to prove a uniform-in-time propagation of chaos for MFLD that takes into account the errors due to finite-particle approximation, time-discretization, and gradient approximation.
arXiv Detail & Related papers (2023-06-12T16:28:11Z) - Diffusion Probabilistic Model Made Slim [128.2227518929644]
We introduce a customized design for slim diffusion probabilistic models (DPM) for light-weight image synthesis.
We achieve 8-18x computational complexity reduction as compared to the latent diffusion models on a series of conditional and unconditional image generation tasks.
arXiv Detail & Related papers (2022-11-27T16:27:28Z) - Spectral Filtering Induced by Non-Hermitian Evolution with Balanced Gain
and Loss: Enhancing Quantum Chaos [4.36777815115981]
nonlinear non-Hermitian evolution with balanced gain and loss can enhance manifestations of quantum chaos.
In the Sachdev-Ye-Kitaev model and random matrix Hamiltonians, BGL increases the span of the ramp, lowering the dip as well as the value of the plateau.
The chaos enhancement due to BGL is optimal over a family of filter functions that can be engineered with fluctuating Hamiltonians.
arXiv Detail & Related papers (2021-08-15T18:00:01Z)
This list is automatically generated from the titles and abstracts of the papers in this site.
This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.