๐ค AI Summary
Modeling high-dimensional dynamical systems from sparse, irregularly timed snapshots remains challenging, especially when dimensionality reduction is undesirable.
Method: We propose Multi-marginal Stochastic Flow Matching (MSFM), a framework that directly learns continuous probabilistic evolution paths in the original high-dimensional spaceโwithout dimensionality reduction. MSFM generalizes simulation-free score matching and flow matching to the multi-marginal setting and incorporates measure-valued splines to explicitly model irregular temporal sampling.
Contribution/Results: By jointly optimizing multi-time marginal distribution constraints and flow consistency, MSFM yields robust, differentiable, and generalizable probability path estimates. Experiments on single-cell gene expression time-series and image evolution tasks demonstrate its ability to accurately recover dynamic structures under non-uniform sampling, while exhibiting strong resistance to overfitting.
๐ Abstract
Modeling the evolution of high-dimensional systems from limited snapshot observations at irregular time points poses a significant challenge in quantitative biology and related fields. Traditional approaches often rely on dimensionality reduction techniques, which can oversimplify the dynamics and fail to capture critical transient behaviors in non-equilibrium systems. We present Multi-Marginal Stochastic Flow Matching (MMSFM), a novel extension of simulation-free score and flow matching methods to the multi-marginal setting, enabling the alignment of high-dimensional data measured at non-equidistant time points without reducing dimensionality. The use of measure-valued splines enhances robustness to irregular snapshot timing, and score matching prevents overfitting in high-dimensional spaces. We validate our framework on several synthetic and benchmark datasets, including gene expression data collected at uneven time points and an image progression task, demonstrating the method's versatility.