Beyond ReLU: Bifurcation, Oversmoothing, and Topological Priors
- URL: http://arxiv.org/abs/2602.15634v1
- Date: Tue, 17 Feb 2026 15:03:28 GMT
- Title: Beyond ReLU: Bifurcation, Oversmoothing, and Topological Priors
- Authors: Erkan Turan, Gaspard Abel, Maysam Behmanesh, Emery Pierson, Maks Ovsjanikov,
- Abstract summary: Graph Neural Networks (GNNs) learn node representations through iterative network-based message-passing.<n>Deep GNNs suffer from oversmoothing, where node features converge to a homogeneous, non-informative state.<n>We re-frame this problem of representational collapse from a emphbifurcation theory perspective, characterizing oversmoothing as convergence to a stable homogeneous fixed point.
- Score: 28.452964044443906
- License: http://creativecommons.org/licenses/by-nc-sa/4.0/
- Abstract: Graph Neural Networks (GNNs) learn node representations through iterative network-based message-passing. While powerful, deep GNNs suffer from oversmoothing, where node features converge to a homogeneous, non-informative state. We re-frame this problem of representational collapse from a \emph{bifurcation theory} perspective, characterizing oversmoothing as convergence to a stable ``homogeneous fixed point.'' Our central contribution is the theoretical discovery that this undesired stability can be broken by replacing standard monotone activations (e.g., ReLU) with a class of functions. Using Lyapunov-Schmidt reduction, we analytically prove that this substitution induces a bifurcation that destabilizes the homogeneous state and creates a new pair of stable, non-homogeneous \emph{patterns} that provably resist oversmoothing. Our theory predicts a precise, nontrivial scaling law for the amplitude of these emergent patterns, which we quantitatively validate in experiments. Finally, we demonstrate the practical utility of our theory by deriving a closed-form, bifurcation-aware initialization and showing its utility in real benchmark experiments.
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