Denseness of operators whose second adjoints attain their numerical radii

Acosta, María D.; Paya, Rafael

doi:10.1090/S0002-9939-1989-0937841-3

Denseness of operators whose second adjoints attain their numerical radii
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by María D. Acosta and Rafael Paya PDF

Proc. Amer. Math. Soc. 105 (1989), 97-101 Request permission

Abstract:

We show that for any Banach space the set of (bounded linear) operators whose second adjoints attain their numerical radii is norm-dense in the space of all operators. In particular, the numerical radius attaining operators on a reflexive space are dense.

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