Subnormal nth roots of quasinormal operators are quasinormal
نویسندگان
چکیده
In a recent paper [11], R.E. Curto, S.H. Lee and J. Yoon asked the following question. Let A be subnormal operator, assume that A2 is quasinormal. Does it follow quasinormal? this paper, we answer question in affirmative. fact, prove more general result nth roots of quasinormal operators are Research on problem has led us to new criterion for semispectral measure half-line spectral, written terms its two “moments”.
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ژورنال
عنوان ژورنال: Journal of Functional Analysis
سال: 2021
ISSN: ['0022-1236', '1096-0783']
DOI: https://doi.org/10.1016/j.jfa.2021.109001