Essentially Normal Operator + Compact Operator = Strongly Irreducible Operator

Jiang, Chunlan; Sun, Shunhua; Wang, Zongyao

doi:10.1090/S0002-9947-97-01754-6

Essentially Normal Operator + Compact Operator = Strongly Irreducible Operator
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by Chunlan Jiang, Shunhua Sun and Zongyao Wang PDF

Trans. Amer. Math. Soc. 349 (1997), 217-233 Request permission

Abstract:

It is shown that given an essentially normal operator $T$ with connected spectrum, there exists a compact operator $K$ such that $T+K$ is strongly irreducible.

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