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On direct sums of reductive operators

Author: Thomas P. Wiggen
Journal: Proc. Amer. Math. Soc. 45 (1974), 313-314
MSC: Primary 47A15
MathSciNet review: 0361837
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Abstract: An example is given to show that the direct sum of two (distinct) reductive operators need not be reductive. The conjecture that $ A \oplus A$ is reductive if $ A$ is reductive is shown to be equivalent to the reductive operator conjecture (every reductive operator is normal).

References [Enhancements On Off] (What's this?)

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