Abstract. In this note, we present several characterizations for some distinguished classes of bounded Hilbert space operators (self-adjoint operators, normal operators, unitary operators, and isometry operators) in terms of operator inequalities.
DOI: 10.14232/actasm-017-773-6
AMS Subject Classification
(1991): 47A30, 47A05, 47B15
Keyword(s):
closed range operator,
Moore-Penrose inverse,
group inverse,
self-adjoint operator,
unitary operator,
normal operator,
partial isometry operator,
isometry operator,
operator inequality
Received April 8, 2017, and in final form November 25, 2017. (Registered under 23/2017.)
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