On the Helton class of 𝑝-hyponormal operators

Kim, Yoenha; Ko, Eungil; Lee, Ji

doi:10.1090/S0002-9939-07-08708-4

On the Helton class of $p$-hyponormal operators
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by Yoenha Kim, Eungil Ko and Ji Eun Lee

Proc. Amer. Math. Soc. 135 (2007), 2113-2120

DOI: https://doi.org/10.1090/S0002-9939-07-08708-4

Published electronically: February 28, 2007

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Abstract:

In this paper we show that the Helton class of $p$-hyponormal operators has scalar extensions. As a corollary we get that each operator in the Helton class of $p$-hyponormal operators has a nontrivial invariant subspace if its spectrum has its interior in the plane.

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