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arXiv · 1705.08967

Applications of amenable semigroups in operator theory

Piotr Niemiec·Paweł Wójcik
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Abstract

The paper deals with continuous homomorphisms $S \ni s \mapsto T_s \in L(E)$ of amenable semigroups $S$ into the algebra $L(E)$ of all bounded linear operators on a Banach space $E$. For a closed linear subspace $F$ of $E$, sufficient conditions are given under which there exists a projection $P \in L(E)$ onto $F$ that commutes with all $T_s$. And when $E$ is a Hilbert space, sufficient conditions are given for the existence of an invertible operator $R \in L(E)$ such that all $R T_s R^{-1}$ are isometries. Also certain results on extending intertwining operators, renorming as well as on operators on hereditarily indecomposable Banach spaces are offered.

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Piotr Niemiec, Paweł Wójcik. 2017-05-24. Applications of amenable semigroups in operator theory. https://doi.org/10.4064/sm180408-26-2

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