Closures of direct sums of classes of operators
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- by Don Hadwin
- Proc. Amer. Math. Soc. 121 (1994), 697-701
- DOI: https://doi.org/10.1090/S0002-9939-1994-1209423-1
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Abstract:
We prove that certain classes of Hilbert space operators that are direct sums of operators in specified classes are closed under sequential $\ast$-strong limits. One such example is the class of operators that are direct sums of operators that are either subnormal or have imaginary parts with spectrum contained in $[0,1] \cup [2,3]$.References
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Bibliographic Information
- © Copyright 1994 American Mathematical Society
- Journal: Proc. Amer. Math. Soc. 121 (1994), 697-701
- MSC: Primary 47D99; Secondary 46H15, 47A15, 47A20
- DOI: https://doi.org/10.1090/S0002-9939-1994-1209423-1
- MathSciNet review: 1209423