How Memory in Optimization Algorithms Implicitly Modifies the Loss
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Abstract (arXiv)
In modern optimization methods used in deep learning, each update depends on the history of previous iterations, often referred to as memory, and this dependence decays fast as the iterates go further into the past. For example, gradient descent with momentum has exponentially decaying memory through exponentially averaged past gradients. We introduce a general technique for identifying a memoryless algorithm that approximates an optimization algorithm with memory. It is obtained by replacing all past iterates in the update by the current one, and then adding a correction term arising from memory (also a function of the current iterate). This correction term can be interpreted as a perturbation of the loss, and the nature of this perturbation can inform how memory implicitly (anti-)regularizes the optimization dynamics. As an application of our theory, we find that Lion does not have the kind of implicit anti-regularization induced by memory that AdamW does, providing a theory-based explanation for Lion's better generalization performance recently documented.
Key facts. Cited by 6 papers in the map (data through 14 Oct 2026). Builds on 51 of its 70 references that are in the map. First posted on arXiv 4 Feb 2025.
Builds on
51 of 70 references.
References · 51
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38 more
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50 most cited of 51 All 51 (JSON)
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Citing papers per year: 2026: 6.
6 papers.
- 2026Clarifying Shampoo: Adapting Spectral Descent to Stochasticity and the Parameter Trajectorycited by 8
- 2026Optimizer Memory Makes Shuffle Order a First-Order Source of Fine-Tuning Noisecited by 7
- 2026The Effect of Mini-Batch Noise on the Implicit Bias of Adamcited by 4
- 2026Stored in Optimizer State, Valued by Later Training: A Causal Account of Subliminal Trait Transfercited by 3
- 2026Same Error, Different Function: The Optimizer as an Implicit Prior in Financial Time Seriescited by 0
- 2026Do Deep Networks Forget Initialization? A Forgetting-Time View of Practical Inductive Biascited by 0
- 2026Stored in Optimizer State, Valued by Later Training: A Causal Account of Subliminal Trait Transfer20 Aug 2026
- 2026Optimizer Memory Makes Shuffle Order a First-Order Source of Fine-Tuning Noise28 Jun 2026
- 2026Do Deep Networks Forget Initialization? A Forgetting-Time View of Practical Inductive Bias27 May 2026
- 2026Same Error, Different Function: The Optimizer as an Implicit Prior in Financial Time Series3 Mar 2026
- 2026Clarifying Shampoo: Adapting Spectral Descent to Stochasticity and the Parameter Trajectory10 Feb 2026
- 2026The Effect of Mini-Batch Noise on the Implicit Bias of Adam2 Feb 2026