English

Random Dot Product Graphs as Dynamical Systems: Limitations and Opportunities

Methodology 2026-03-09 v1 Machine Learning Statistics Theory Statistics Theory

Abstract

Can we learn the differential equations governing the evolution of a temporal network? We investigate this within Random Dot Product Graphs (RDPGs), where each network snapshot is generated from latent positions evolving under unknown dynamics. We identify three fundamental obstructions: gauge freedom from rotational ambiguity in latent positions, realizability constraints from the manifold structure of the probability matrix, and trajectory recovery artifacts from spectral embedding. We develop a geometric framework based on principal fiber bundles that formalizes these obstructions. We characterize invisible dynamics as exactly the skew-symmetric generators, and show the realizable tangent space has dimension ndd(d1)/2nd - d(d-1)/2. An holonomy dichotomy emerges: polynomial dynamics have commuting generators, stationary eigenvectors, and trivial holonomy, making gauge alignment purely statistical; Laplacian dynamics satisfy a non-commutativity criterion producing nontrivial holonomy, with curvature weighted by 1/(λι+λγ)1/(\lambda_\iota + \lambda_\gamma) linking gauge sensitivity to the spectral gap. In d=2d=2 this yields full restricted holonomy SO(2)\mathrm{SO}(2); for d3d \ge 3 generic full SO(d)\mathrm{SO}(d) remains conjectural. Cram'er--Rao lower bounds reveal that the same spectral gap controlling curvature and injectivity simultaneously controls Fisher information, so geometric and statistical difficulty are inextricable. We prove an identifiability principle: symmetric dynamics cannot absorb skew-symmetric gauge contamination, so dynamics structure can resolve gauge ambiguity. We demonstrate this constructively with anchor-based alignment and a UDE pipeline recovering vector fields from noisy graph sequences. Yet finite-sample interactions between noise, gauge, and dynamics expressiveness remain beyond the asymptotic theory. We frame this gap as an open challenge.

Keywords

Cite

@article{arxiv.2603.05703,
  title  = {Random Dot Product Graphs as Dynamical Systems: Limitations and Opportunities},
  author = {Giulio Valentino Dalla Riva},
  journal= {arXiv preprint arXiv:2603.05703},
  year   = {2026}
}

Comments

39 pages, 3 figures

R2 v1 2026-07-01T11:05:48.172Z