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arXiv · 2509.10450

A linear-time algorithm for Chow decompositions

Alexander Taveira Blomenhofer·Benjamin Lovitz
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Abstract

We propose a linear-time algorithm to compute low-rank Chow decompositions. Our algorithm can decompose concise symmetric 3-tensors in n variables of Chow rank n/3. The algorithm is pencil based, hence it relies on generalized eigenvalue computations. We also develop sub-quadratic time algorithms for higher order Chow decompositions, and Chow decompositions of 3-tensors into products of linear forms which do not lie on the generic orbit. In particular, we obtain a sub-quadratic-time algorithm for decomposing a symmetric 3-tensor into a linear combination of W-tensors.

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Alexander Taveira Blomenhofer, Benjamin Lovitz. 2025-09-12. A linear-time algorithm for Chow decompositions. https://arxiv.org/abs/2509.10450

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