CHARACTERIZATIONS OF OPERATOR ORDER FOR k STRICTLY POSITIVE OPERATORS
نویسندگان
چکیده
Let Ai (i = 1,2, · · · ,k) be bounded linear operators on a Hilbert space. This paper aims to show a characterization of operator order Ak Ak−1 · · · A2 A1 > 0 in terms of operator inequalities. Afterwards, an application of the characterization is given to operator equalities due to Douglas’s majorization and factorization theorem. Mathematics subject classification (2010): 47A63.
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