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arXiv · 2505.07137

Triangulating PL functions and the existence of efficient ReLU DNNs

Danny Calegari
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Abstract

We show that every piecewise linear function $f:R^d \to R$ with compact support a polyhedron $P$ has a representation as a sum of so-called `simplex functions'. Such representations arise from degree 1 triangulations of the relative homology class (in $R^{d+1}$) bounded by $P$ and the graph of $f$, and give a short elementary proof of the existence of efficient universal ReLU neural networks that simultaneously compute all such functions $f$ of bounded complexity.

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Danny Calegari. 2025-05-11. Triangulating PL functions and the existence of efficient ReLU DNNs. https://arxiv.org/abs/2505.07137

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