| Title:
|
Numerical range of operators acting on Banach spaces (English) |
| Author:
|
Jahedi, Khadijeh |
| Author:
|
Yousefi, Bahmann |
| Language:
|
English |
| Journal:
|
Czechoslovak Mathematical Journal |
| ISSN:
|
0011-4642 (print) |
| ISSN:
|
1572-9141 (online) |
| Volume:
|
62 |
| Issue:
|
2 |
| Year:
|
2012 |
| Pages:
|
495-503 |
| Summary lang:
|
English |
| . |
| Category:
|
math |
| . |
| Summary:
|
The aim of the paper is to propose a definition of numerical range of an operator on reflexive Banach spaces. Under this definition the numerical range will possess the basic properties of a canonical numerical range. We will determine necessary and sufficient conditions under which the numerical range of a composition operator on a weighted Hardy space is closed. We will also give some necessary conditions to show that when the closure of the numerical range of a composition operator on a small weighted Hardy space has zero. (English) |
| Keyword:
|
numerical range |
| Keyword:
|
weighted Hardy space |
| Keyword:
|
compact operator |
| Keyword:
|
composition operator |
| MSC:
|
30H10 |
| MSC:
|
47A12 |
| MSC:
|
47B33 |
| MSC:
|
47B37 |
| idZBL:
|
Zbl 1259.47009 |
| idMR:
|
MR2990189 |
| DOI:
|
10.1007/s10587-012-0024-7 |
| . |
| Date available:
|
2012-06-08T09:49:02Z |
| Last updated:
|
2020-07-03 |
| Stable URL:
|
http://hdl.handle.net/10338.dmlcz/142841 |
| . |
| Reference:
|
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