Idempotency of linear combinations of three idempotent matrices, two of which are disjoint (Q1881058)
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scientific article; zbMATH DE number 2105733
| Language | Label | Description | Also known as |
|---|---|---|---|
| English | Idempotency of linear combinations of three idempotent matrices, two of which are disjoint |
scientific article; zbMATH DE number 2105733 |
Statements
Idempotency of linear combinations of three idempotent matrices, two of which are disjoint (English)
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4 October 2004
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Let \(A_1\), \(A_2\) and \(A_3\) be nonzero idempotent \(n\times n\) complex matrices such that \(A_2A_3=A_3A_2=0\). The author gives a characterization for the idempotency of the matrix \(c_1A_1+c_2A_2+c_3A_3\), where \(c_1,c_2\) and \(c_3\) are nonzero complex numbers.
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projector
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commutativity of projectors
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linear combination of chi-square distributed quadratic forms
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idempotency
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