English

Generalized Module Extension Banach Algebras: Derivations and Weak Amenability

Functional Analysis 2016-08-22 v1

Abstract

Let AA and XX be Banach algebras and let XX be an algebraic Banach AA-module. Then the 1\ell^1-direct sum A×XA\times X equipped with the multiplication (a,x)(b,y)=(ab,ay+xb+xy)(a,bA,x,yX)(a,x)(b,y)=(ab, ay+xb+xy)\quad (a,b\in A, x,y\in X) is a Banach algebra, denoted by AXA\bowtie X, which will be called "\textit{a generalized module extension Banach algebra}". Module extension algebras, Lau product and also the direct sum of Banach algebras are the main examples satisfying this framework. We characterize the structure of nn-dual valued (nN)n\in\mathbb N)) derivations on AXA\bowtie X from which we investigate the nn-weak amenability for the algebra AX.A\bowtie X. We apply the results and the techniques of proofs for presenting some older results with simple direct proofs.

Keywords

Cite

@article{arxiv.1608.05530,
  title  = {Generalized Module Extension Banach Algebras: Derivations and Weak Amenability},
  author = {Mohammad Ramezanpour and Seddigheh Barootkoob},
  journal= {arXiv preprint arXiv:1608.05530},
  year   = {2016}
}

Comments

9 pages, To appear in Quaest Math

R2 v1 2026-06-22T15:24:08.240Z