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Start Over Creator Yousefi, Bahmann

1. Hypercyclicity of special operators on Hilbert function spaces

Creator:
Yousefi, Bahmann and Haghkhah, S.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
multiplier, orbit, hypercyclic vector, multiplication operator, and weighted composition operator
Language:
English
Description:
In this paper we give some sufficient conditions for the adjoint of a weighted composition operator on a Hilbert space of analytic functions to be hypercyclic.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

2. Numerical range of operators acting on Banach spaces

Creator:
Jahedi, Khadijeh and Yousefi, Bahmann
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
numerical range, weighted Hardy space, compact operator, and composition operator
Language:
English
Description:
The aim of the paper is to propose a definition of numerical range of an operator on reflexive Banach spaces. Under this definition the numerical range will possess the basic properties of a canonical numerical range. We will determine necessary and sufficient conditions under which the numerical range of a composition operator on a weighted Hardy space is closed. We will also give some necessary conditions to show that when the closure of the numerical range of a composition operator on a small weighted Hardy space has zero.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public