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arXiv · 2502.05656

Flowing Through Layers: A Continuous Dynamical Systems Perspective on Transformers

Jacob Fein-Ashley
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Abstract

We show that the standard discrete update rule of transformer layers can be naturally interpreted as a forward Euler discretization of a continuous dynamical system. Our Transformer Flow Approximation Theorem demonstrates that, under standard Lipschitz continuity assumptions, token representations converge uniformly to the unique solution of an ODE as the number of layers grows. Moreover, if the underlying mapping satisfies a one-sided Lipschitz condition with a negative constant, the resulting dynamics are contractive, causing perturbations to decay exponentially across layers. Beyond clarifying the empirical stability and expressivity of transformer models, these insights link transformer updates to a broader iterative reasoning framework, suggesting new avenues for accelerated convergence and architectural innovations inspired by dynamical systems theory.

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Jacob Fein-Ashley. 2025-02-08. Flowing Through Layers: A Continuous Dynamical Systems Perspective on Transformers. https://arxiv.org/abs/2502.05656

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