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arXiv · 1302.0602

Decomposition of Singular Matrices into Idempotents

Adel Alahmadi·Surender Jain·André Leroy
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Abstract

In this paper we provide concrete constructions of idempotents to represent typical singular matrices over a given ring as a product of idempotents and apply these factorizations for proving our main results. We generalize works due to Laffey (Products of idempotent matrices. Linear Multilinear A. 1983) and Rao (Products of idempotent matrices. Linear Algebra Appl. 2009) to noncommutative setting and fill in the gaps in the original proof of Rao's main theorems. We also consider singular matrices over Bézout domains as to when such a matrix is a product of idempotent matrices.

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Adel Alahmadi, Surender Jain, André Leroy. 2013-02-04. Decomposition of Singular Matrices into Idempotents. https://doi.org/10.1080/03081087.2012.754439

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