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arXiv · 1409.8203

Splittings of extensions and homological bidimension of the algebra of bounded operators on a Banach space

Niels Jakob Laustsen·Richard Skillicorn
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Abstract

We show that there exists a Banach space $E$ with the following properties: the Banach algebra $\mathscr{B}(E)$ of bounded, linear operators on $E$ has a singular extension which splits algebraically, but it does not split strongly, and the homological bidimension of $\mathscr{B}(E)$ is at least two. The first of these conclusions solves a natural problem left open by Bade, Dales, and Lykova (Mem. Amer. Math. Soc. 1999), while the second answers a question of Helemskii. The Banach space $E$ that we use was originally introduced by Read (J. London Math. Soc. 1989).

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Niels Jakob Laustsen, Richard Skillicorn. 2014-09-29. Splittings of extensions and homological bidimension of the algebra of bounded operators on a Banach space. https://doi.org/10.1016/j.crma.2015.12.020

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