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Start Over Creator Robati, Bahram Khani

1. Cyclicity of the adjoint of weighted composition operators on the Hilbert space of analytic functions

Creator:
Kamali, Zahra, Robati, Bahram Khani, and Hedayatian, Karim
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
hypercyclicity, supercyclicity, cyclicity, and weighted composition operators
Language:
English
Description:
In this paper, we discuss the hypercyclicity, supercyclicity and cyclicity of the adjoint of a weighted composition operator on a Hilbert space of analytic functions.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

2. Essential normality for certain finite linear combinations of linear-fractional composition operators on the Hardy space $H^{2}$

Creator:
Fatehi, Mahsa and Robati, Bahram Khani
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
Hardy spaces, essentially normal, composition operator, and linear-fractional transformation
Language:
English
Description:
In 1999 Nina Zorboska and in 2003 P. S. Bourdon, D. Levi, S. K. Narayan and J. H. Shapiro investigated the essentially normal composition operator $C_{\varphi }$, when $\varphi $ is a linear-fractional self-map of $\mathbb {D}$. In this paper first, we investigate the essential normality problem for the operator $T_{w}C_{\varphi }$ on the Hardy space $H^{2}$, where $w$ is a bounded measurable function on $\partial \mathbb {D}$ which is continuous at each point of $F(\varphi )$, $\varphi \in {\cal S}(2)$, and $T_{w}$ is the Toeplitz operator with symbol $w$. Then we use these results and characterize the essentially normal finite linear combinations of certain linear-fractional composition operators on $H^{2}$.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

3. Non supercyclic subsets of linear isometries on Banach spaces of analytic functions

Creator:
Moradi, Abbas, Hedayatian, Karim, Robati, Bahram Khani, and Ansari, Mohammad
Format:
print, bez média, and svazek
Type:
model:article and TEXT
Subject:
matematika, mathematics, supercyclicity, hypercyclic operator, semigroup, isometry, 13, and 51
Language:
English
Description:
Let X be a Banach space of analytic functions on the open unit disk and Γ a subset of linear isometries on X. Sufficient conditions are given for non-supercyclicity of Γ. In particular, we show that the semigroup of linear isometries on the spaces S^{p} (p>1), the little Bloch space, and the group of surjective linear isometries on the big Bloch space are not supercyclic. Also, we observe that the groups of all surjective linear isometries on the Hardy space H^{p} or the Bergman space L_{a}^{p} (1< p< ∞,p\neq 2) are not supercyclic., Abbas Moradi, Karim Hedayatian, Bahram Khani Robati, Mohammad Ansari., and Obsahuje seznam literatury
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public