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arXiv · 2405.00778

Rigidity matroids and linear algebraic matroids with applications to matrix completion and tensor codes

Joshua Brakensiek·Manik Dhar·Jiyang Gao·Sivakanth Gopi·Matt Larson
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Abstract

We establish a connection between problems studied in rigidity theory and matroids arising from linear algebraic constructions like tensor products and symmetric products. A special case of this correspondence identifies the problem of giving a description of the correctable erasure patterns in a maximally recoverable tensor code with the problem of describing bipartite rigid graphs or low-rank completable matrix patterns. Additionally, we relate dependencies among symmetric products of generic vectors to graph rigidity and symmetric matrix completion. With an eye toward applications to computer science, we study the dependency of these matroids on the characteristic by giving new combinatorial descriptions in several cases, including the first description of the correctable patterns in an (m, n, a=2, b=2) maximally recoverable tensor code.

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Joshua Brakensiek, Manik Dhar, Jiyang Gao, Sivakanth Gopi, Matt Larson. 2024-05-01. Rigidity matroids and linear algebraic matroids with applications to matrix completion and tensor codes. https://arxiv.org/abs/2405.00778

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