| Title: | On a certain class of subspectra (English) | 
| Author: | Sołtysiak, Andrzej | 
| Language: | English | 
| Journal: | Commentationes Mathematicae Universitatis Carolinae | 
| ISSN: | 0010-2628 (print) | 
| ISSN: | 1213-7243 (online) | 
| Volume: | 32 | 
| Issue: | 4 | 
| Year: | 1991 | 
| Pages: | 715-721 | 
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| Category: | math | 
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| Summary: | The aim of this paper is to characterize a class of subspectra for which the geometric spectral radius is the same and depends only upon a commuting $n$-tuple of elements of a complex Banach algebra. We prove also that all these subspectra have the same capacity. (English) | 
| Keyword: | Banach algebra | 
| Keyword: | joint spectrum | 
| Keyword: | subspectrum | 
| Keyword: | spectroid | 
| Keyword: | geometrical spectral radius | 
| Keyword: | (joint) capacity | 
| MSC: | 46H05 | 
| MSC: | 46H30 | 
| MSC: | 47A13 | 
| idZBL: | Zbl 0763.46037 | 
| idMR: | MR1159818 | 
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| Date available: | 2009-01-08T17:48:31Z | 
| Last updated: | 2012-04-30 | 
| Stable URL: | http://hdl.handle.net/10338.dmlcz/118451 | 
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