Factoring a Quadratic Operator as a Product of Two Positive Contractions
2016 ◽
Vol 59
(2)
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pp. 354-362
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Keyword(s):
AbstractLet T be a quadratic operator on a complex Hilbert space H. We show that T can be written as a product of two positive contractions if and only if T is of the formfor some a, b ∊ [0, 1] and strictly positive operator P with . Also, we give a necessary condition for a bounded linear operator T with operator matrix on H⊕K that can be written as a product of two positive contractions.
1969 ◽
Vol 21
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pp. 1421-1426
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Keyword(s):
1969 ◽
Vol 12
(5)
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pp. 639-643
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1974 ◽
Vol 76
(2)
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pp. 415-416
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1977 ◽
Vol 29
(5)
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pp. 1010-1030
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2006 ◽
Vol 136
(5)
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pp. 935-944
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