A Diagrammatic Approach to Improve Computational Efficiency in Group Equivariant Neural Networks

Edward Pearce-Crump; William J. Knottenbelt

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arXiv · 2412.10837

A Diagrammatic Approach to Improve Computational Efficiency in Group Equivariant Neural Networks

Edward Pearce-Crump·William J. Knottenbelt

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Abstract

Group equivariant neural networks are growing in importance owing to their ability to generalise well in applications where the data has known underlying symmetries. Recent characterisations of a class of these networks that use high-order tensor power spaces as their layers suggest that they have significant potential; however, their implementation remains challenging owing to the prohibitively expensive nature of the computations that are involved. In this work, we present a fast matrix multiplication algorithm for any equivariant weight matrix that maps between tensor power layer spaces in these networks for four groups: the symmetric, orthogonal, special orthogonal, and symplectic groups. We obtain this algorithm by developing a diagrammatic framework based on category theory that enables us to not only express each weight matrix as a linear combination of diagrams but also makes it possible for us to use these diagrams to factor the original computation into a series of steps that are optimal. We show that this algorithm improves the Big-$O$ time complexity exponentially in comparison to a naïve matrix multiplication.

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BibTeX RIS

Edward Pearce-Crump, William J. Knottenbelt. 2024-12-14. A Diagrammatic Approach to Improve Computational Efficiency in Group Equivariant Neural Networks. https://arxiv.org/abs/2412.10837

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