منابع مشابه
Isometric weighted composition operators
A composition operator is an operator on a space of functions defined on the same set. Its action is by composition to the right with a fixed selfmap of that set. A composition operator followed by a multiplication operator is called a weighted composition operator. In this paper, we study when weighted composition operators on the Hilbert Hardy space of the open unit disc are isometric. We fin...
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Let $mathcal{A}$ be a commutative Banach algebra and $mathscr{X}$ be a left Banach $mathcal{A}$-module. We study the set ${rm Dec}_{mathcal{A}}(mathscr{X})$ of all elements in $mathcal{A}$ which induce a decomposable multiplication operator on $mathscr{X}$. In the case $mathscr{X}=mathcal{A}$, ${rm Dec}_{mathcal{A}}(mathcal{A})$ is the well-known Apostol algebra of $mathcal{A}$. We s...
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متن کاملmultiplication operators on banach modules over spectrally separable algebras
let $pa$ be a commutative banach algebra and $ex$ be a left banach $pa$-module. we study the set $dec_{pa}(ex)$ of all elements in $pa$ which induce a decomposable multiplication operator on $ex$. in the case $ex=pa$, $dec_{pa}(pa)$ is the well-known apostol algebra of $pa$. we show that $dec_{pa}(ex)$ is intimately related with the largest spectrally separable subalgebra of $pa$ and...
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ژورنال
عنوان ژورنال: Studia Mathematica
سال: 2017
ISSN: 0039-3223,1730-6337
DOI: 10.4064/sm8538-6-2016