Symmetry in Neural Network Parameter Spaces

Bo Zhao; Robin Walters; Rose Yu

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arXiv · 2506.13018

Symmetry in Neural Network Parameter Spaces

Bo Zhao·Robin Walters·Rose Yu

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Abstract

Modern deep learning models are highly overparameterized, resulting in large sets of parameter configurations that yield the same outputs. A significant portion of this redundancy is explained by symmetries in the parameter space--transformations that leave the network function unchanged. These symmetries shape the loss landscape and constrain learning dynamics, offering a new lens for understanding optimization, generalization, and model complexity that complements existing theory of deep learning. This survey provides an overview of parameter space symmetry. We summarize existing literature, uncover connections between symmetry and learning theory, and identify gaps and opportunities in this emerging field.

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Bo Zhao, Robin Walters, Rose Yu. 2025-06-16. Symmetry in Neural Network Parameter Spaces. https://arxiv.org/abs/2506.13018

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