Remarks on “Operators with inverses similar to their adjoints”

DePrima, C. R.

doi:10.1090/S0002-9939-1974-0331080-4

Remarks on “Operators with inverses similar to their adjoints”
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by C. R. DePrima PDF

Proc. Amer. Math. Soc. 43 (1974), 478-480 Request permission

Abstract:

A result in the cited paper [7] which purports to furnish a sufficient condition for an operator $T$ on a Hilbert space $\mathfrak {H}$ for which ${T^{ - 1}}S = S{T^ \ast }$ with $0 \notin \operatorname {cl} (W(S))$ to be unitary is shown to be false. Various conditions under which such a result does hold are explored.

References

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