A Closed-Form Upper Bound for Admissible Learning-Rate Steps in Belief-Space Dynamics

Zixi Li; Youzhen Li

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arXiv · 2605.06741

A Closed-Form Upper Bound for Admissible Learning-Rate Steps in Belief-Space Dynamics

Zixi Li·Youzhen Li

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Abstract

Learning-rate steps are usually treated as hyperparameters. This paper isolates a local beliefspace calculation: when an update is modeled as a projected forward step on the probability simplex, admissibility means contractivity in the natural KL/Bregman geometry. Under this model, the upper bound of an admissible step is not a tuning slogan but a formula.

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Zixi Li, Youzhen Li. 2026-05-07. A Closed-Form Upper Bound for Admissible Learning-Rate Steps in Belief-Space Dynamics. https://arxiv.org/abs/2605.06741

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