Triangular truncation and normal limits of nilpotent operators

Author:
Don Hadwin

Journal:
Proc. Amer. Math. Soc. **123** (1995), 1741-1745

MSC:
Primary 47A58; Secondary 15A60, 47A30, 47A65

MathSciNet review:
1257109

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Abstract | References | Similar Articles | Additional Information

Abstract: We show that, as , the product of the norm of the triangular truncation map on the complex matrices with the distance from the norm-one hermitian matrices to the nilpotents converges to 1/2. We also include an elementary proof of D. Herrero's characterization of the normal operators that are norm limits of nilpotents.

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DOI:
http://dx.doi.org/10.1090/S0002-9939-1995-1257109-0

Article copyright:
© Copyright 1995
American Mathematical Society