A simple proof of an extension of the Fuglede-Putnam theorem

Gong, Wei Bang

doi:10.1090/S0002-9939-1987-0891172-7

A simple proof of an extension of the Fuglede-Putnam theorem
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Proc. Amer. Math. Soc. 100 (1987), 599-600 Request permission

Abstract:

A simple proof is given of the Theorem. If $A$ and ${B^ * }$ are hyponormal, then ${\left \| {AX - XB} \right \|_2} \geq {\left \| {{A^ * }X - X{B^ * }} \right \|_2}$ for every $X$ in the Hilbert-Schmidt class.

References

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