Amenability constants for unconditional sums of Banach algebras

arXiv (Cornell University) 2026 Preprint Open access

Read full text
Authors: Tomasz Kania, Jerzy Kąkol
Cited by: 0

Abstract

We study Johnson amenability for unconditional direct sums of Banach algebras. Given a family $(A_i)_{i\in I}$ of Banach algebras and a Banach sequence lattice $E$ on~$I$, the $E$-sum $\bigl(\bigoplus_{i\in I} A_i\bigr)_{\!E}$ carries a natural Banach algebra structure via coordinatewise multiplication. Under the hypothesis that $C_E := \sup\{\|χ_F\|_E: F\subseteq I\text{ finite}\}

Fields of Study & Subjects

Advanced Banach Space Theory Advanced Operator Algebra Research Holomorphic and Operator Theory

Publication details

Journal / source
arXiv (Cornell University)
Publication date
10 January 2026
Document type
Preprint