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arXiv · 1906.05757

The rank of sparse random matrices

Amin Coja-Oghlan·Alperen A. Ergür·Pu Gao·Samuel Hetterich·Maurice Rolvien
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Abstract

We determine the rank of a random matrix over an arbitrary field with prescribed numbers of non-zero entries in each row and column. As an application we obtain a formula for the rate of low-density parity check codes. This formula vindicates a conjecture of Lelarge (2013). The proofs are based on coupling arguments and a novel random perturbation, applicable to any matrix, that diminishes the number of short linear relations.

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Amin Coja-Oghlan, Alperen A. Ergür, Pu Gao, Samuel Hetterich, Maurice Rolvien. 2024-06-19. The rank of sparse random matrices. https://arxiv.org/abs/1906.05757

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