HYPEREXPANSIVE OPERATOR VALUED UNILATERAL WEIGHTED SHIFTS
نویسندگان
چکیده
منابع مشابه
k-HYPONORMALITY OF FINITE RANK PERTURBATIONS OF UNILATERAL WEIGHTED SHIFTS
Abstract. In this paper we explore finite rank perturbations of unilateral weighted shifts Wα. First, we prove that the subnormality of Wα is never stable under nonzero finite rank pertrubations unless the perturbation occurs at the zeroth weight. Second, we establish that 2-hyponormality implies positive quadratic hyponormality, in the sense that the Maclaurin coefficients ofDn(s) := detPn [(W...
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ژورنال
عنوان ژورنال: Glasgow Mathematical Journal
سال: 2004
ISSN: 0017-0895,1469-509X
DOI: 10.1017/s0017089504001892