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arXiv · 2610.13341

Understanding Mamba-3 Through Oscillatory Dynamics

Shutian Liang·Yue Song
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Abstract

Mamba-3 introduces input-dependent rotations into recurrent state updates, but their contribution beyond state retention remains unclear. We interpret these ro- tations as underdamped second-order dynamics, providing a framework for in- vestigating the role of oscillation in sequence modeling. Controlled comparisons show that underdamped dynamics outperform non-oscillatory damping regimes on state-tracking tasks, while language-model pretraining demonstrates benefits for long-context prediction and length generalization. Interventions in pretrained models further establish the importance of learned phase, and state analysis sug- gests that rotation regulates how retained information combines with incoming up- dates. Taken together, these findings identify underdamped dynamics as a useful mechanism for recurrent computation and suggest that oscillation supports long- context processing by regulating how information accumulates.

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Shutian Liang, Yue Song. 2026-10-09. Understanding Mamba-3 Through Oscillatory Dynamics. https://arxiv.org/abs/2610.13341

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