DuSEGO: Dual Second-order Equivariant Graph Ordinary Differential Equation
Yingxu Wang, Nan Yin, Mingyan Xiao, Xinhao Yi, Siwei Liu, Shangsong Liang
TL;DR
DuSEGO addresses limitations of equivariant GNNs by introducing dual second-order graph ODEs that evolve both node coordinates and features, preserving equivariance while mitigating over-smoothing and gradient instability. The method plugs in any equivariant backbone (EGNN or SEGNN) and solves coupled second-order dynamics for $\mathbf{X}$ and $\mathbf{H}$, yielding richer temporal trajectories than traditional multi-layer GNNs. Theoretical guarantees include equivariance preservation and gradient-stability properties, while empirical results across dynamic-system modeling, graph autoencoding, and molecular property prediction show improved accuracy, data efficiency, and robustness to depth. These findings suggest DuSEGO as a flexible, physics-inspired framework for high-order graph dynamics with broad applicability in complex physical and molecular domains.
Abstract
Graph Neural Networks (GNNs) with equivariant properties have achieved significant success in modeling complex dynamic systems and molecular properties. However, their expressiveness ability is limited by: (1) Existing methods often overlook the over-smoothing issue caused by traditional GNN models, as well as the gradient explosion or vanishing problems in deep GNNs. (2) Most models operate on first-order information, neglecting that the real world often consists of second-order systems, which further limits the model's representation capabilities. To address these issues, we propose the \textbf{Du}al \textbf{S}econd-order \textbf{E}quivariant \textbf{G}raph \textbf{O}rdinary Differential Equation (\method{}) for equivariant representation. Specifically, \method{} apply the dual second-order equivariant graph ordinary differential equations (Graph ODEs) on graph embeddings and node coordinates, simultaneously. Theoretically, we first prove that \method{} maintains the equivariant property. Furthermore, we provide theoretical insights showing that \method{} effectively alleviates the over-smoothing problem in both feature representation and coordinate update. Additionally, we demonstrate that the proposed \method{} mitigates the exploding and vanishing gradients problem, facilitating the training of deep multi-layer GNNs. Extensive experiments on benchmark datasets validate the superiority of the proposed \method{} compared to baselines.
