Operator Ideals, Orthonormal Systems and
β
Franziska Baur
π
Article
π
1999
π
John Wiley and Sons
π
English
β 429 KB
## Abstract Given an orthonormal system __B__ in some __L__^2^(__u__) we consider the operator ideals II~B~ and __T__~B~ of __B__βsumming and __B__βtype operators and some related ideals. We characterize by certain weak compactness properties when II~B~ is equal to the operator ideal II~2~ of 2βsum