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

Abstract

We show that there exists a Banach space $E$ with the following properties: the Banach algebra $\mathcal{B}(E)$ of bounded, linear operators on $E$ has a singular extension which splits algebraically, but it does not split strongly, and the homological bidimension of $\mathcal{B}(E)$ 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).

arXiv commentto appear in C.R. Math. Acad. Sci. Paris

Cited by in corpus (1)

• A singular, admissible extension which splits algebraically, but not strongly, of the algebra of bounded operators on a Banach space