| Title:
             | 
Unconditional ideals of finite rank operators (English) | 
| Author:
             | 
Abrahamsen, Trond A. | 
| Author:
             | 
Lima, Asvald | 
| Author:
             | 
Lima, Vegard | 
| Language:
             | 
English | 
| Journal:
             | 
Czechoslovak Mathematical Journal | 
| ISSN:
             | 
0011-4642 (print) | 
| ISSN:
             | 
1572-9141 (online) | 
| Volume:
             | 
58 | 
| Issue:
             | 
4 | 
| Year:
             | 
2008 | 
| Pages:
             | 
1257-1278 | 
| Summary lang:
             | 
English | 
| . | 
| Category:
             | 
math | 
| . | 
| Summary:
             | 
Let $X$ be a Banach space. We give characterizations of when ${\cal F}(Y,X)$ is a $u$-ideal in ${\cal W}(Y,X)$ for every Banach space $Y$ in terms of nets of finite rank operators approximating weakly compact operators. Similar characterizations are given for the cases when ${\cal F}(X,Y)$ is a $u$-ideal in ${\cal W}(X,Y)$ for every Banach space $Y$, when ${\cal F}(Y,X)$ is a $u$-ideal in ${\cal W}(Y,X^{**})$ for every Banach space $Y$, and when ${\cal F}(Y,X)$ is a $u$-ideal in ${\cal K}(Y,X^{**})$ for every Banach space $Y$. (English) | 
| Keyword:
             | 
$u$-ideals | 
| Keyword:
             | 
finite rank | 
| Keyword:
             | 
compact | 
| Keyword:
             | 
and weakly compact operators | 
| Keyword:
             | 
Hahn-Banach extension operators | 
| MSC:
             | 
46B04 | 
| MSC:
             | 
46B20 | 
| MSC:
             | 
46B28 | 
| MSC:
             | 
47L20 | 
| idZBL:
             | 
Zbl 1174.46003 | 
| idMR:
             | 
MR2471182 | 
| . | 
| Date available:
             | 
2010-07-21T08:18:50Z | 
| Last updated:
             | 
2020-07-03 | 
| Stable URL:
             | 
http://hdl.handle.net/10338.dmlcz/140456 | 
| . | 
| Reference:
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| . |