A Remedy for Over-Squashing in Graph Learning via Forman-Ricci Curvature based Graph-to-Hypergraph Structural Lifting
Graph neural networks (GNNs) suffer from the “over-squashing” problem—severe distortion of long-range node information during neighborhood aggregation—hindering effective modeling of distant dependencies. To address this, we propose a geometry-driven graph structural enhancement method: for the first time, we integrate Forman-Ricci curvature into GNN preprocessing to identify backbone substructures; guided by curvature, we perform graph coarsening and hyperedge generation to construct topology-preserving high-order hypergraph representations. Crucially, our approach enhances cross-community information flow explicitly without modifying the underlying GNN architecture. Extensive experiments on multiple benchmark datasets demonstrate that our method significantly alleviates over-squashing, yielding average accuracy improvements of 3.2–7.8% on long-range reasoning tasks—including graph classification and link prediction—thereby validating the efficacy and generalizability of geometric priors in structural optimization.