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Every matrix is a linear combination of three idempotents

✍ Scribed by Vyacheslav Rabanovich


Publisher
Elsevier Science
Year
2004
Tongue
English
Weight
173 KB
Volume
390
Category
Article
ISSN
0024-3795

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✦ Synopsis


It is shown that every n Γ— n matrix over a field of characteristic zero is a linear combination of three idempotent matrices. It is proved that both 2 Γ— 2 matrices and complex 3 Γ— 3 matrices are linear combinations of two idempotents. Also we present 3 Γ— 3 and 4 Γ— 4 matrices that are not linear combinations of any two idempotents.


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