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arXiv · 1711.03482

Light groups of isomorphisms of Banach spaces and invariant LUR renormings

Leandro Antunes·Valentin Ferenczi·Sophie Grivaux·Christian Rosendal
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Abstract

Megrelishvili defines \emph{light groups} of isomorphisms of a Banach space as the groups on which the Weak and Strong Operator Topologies coincide, and proves that every bounded group of isomorphisms of Banach spaces with the Point of Continuity Property (PCP) is light. We investigate this concept for isomorphism groups $G$ of classical Banach spaces $X$ without the PCP, specially isometry groups, and relate it to the existence of $G$-invariant LUR or strictly convex renormings of $X$.

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Leandro Antunes, Valentin Ferenczi, Sophie Grivaux, Christian Rosendal. 2017-11-09. Light groups of isomorphisms of Banach spaces and invariant LUR renormings. https://doi.org/10.2140/pjm.2019.301.31

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