Approximate amenability is not bounded approximate amenability

被引:4
|
作者
Ghahramani, F. [1 ]
Read, C. J. [2 ]
机构
[1] Univ Manitoba, Dept Math, Winnipeg, MB R3T 2N2, Canada
[2] Univ Leeds, Dept Pure Math, Leeds LS2 9JT, W Yorkshire, England
基金
加拿大自然科学与工程研究理事会;
关键词
Approximately amenable Banach algebra; Approximate diagonal; Boundedly approximately amenable; Banach algebras; Approximate identity; ALGEBRAS;
D O I
10.1016/j.jmaa.2014.09.060
中图分类号
O29 [应用数学];
学科分类号
070104 ;
摘要
We obtain a new criterion sufficient for approximate amenability of Banach algebras, and an associated criterion sufficient for approximate amenability of co-direct sums of approximately amenable Banach algebras. We use these criteria to give examples of Banach algebras which are approximately amenable, but not boundedly approximately amenable. Thus we answer a question which was open since the year 2004. This is, so to speak, the complementary result to one of our earlier ones in the paper [F. Ghahramani, C.J. Read, Approximate identities in approximate amenability, J. Funct. Anal. 262 (9) (2012) 3929-3945], where we gave examples of boundedly approximately amenable Banach algebras that are not boundedly approximately contractible. (C) 2014 Elsevier Inc. All rights reserved.
引用
收藏
页码:106 / 119
页数:14
相关论文
共 50 条