| Title: | On unitary convex decompositions of vectors in a $JB^{*}$-algebra (English) | 
| Author: | Siddiqui, Akhlaq A. | 
| Language: | English | 
| Journal: | Archivum Mathematicum | 
| ISSN: | 0044-8753 (print) | 
| ISSN: | 1212-5059 (online) | 
| Volume: | 49 | 
| Issue: | 2 | 
| Year: | 2013 | 
| Pages: | 79-86 | 
| Summary lang: | English | 
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| Category: | math | 
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| Summary: | By exploiting his recent results, the author further investigates the extent to which variation in the coefficients of a unitary convex decomposition of a vector in a unital $JB^{*}$-algebra permits the vector decomposable as convex combination of fewer unitaries; certain $ C^{*}$-algebra results due to M. Rørdam have been extended to the general setting of $JB^{*}$-algebras. (English) | 
| Keyword: | $C^{*}$-algebra | 
| Keyword: | $JB^{*}$-algebra | 
| Keyword: | unit ball | 
| Keyword: | invertible element | 
| Keyword: | unitary element | 
| Keyword: | unitary isotope | 
| Keyword: | convex hull | 
| Keyword: | unitary rank | 
| Keyword: | unitary convex decomposition | 
| MSC: | 17C65 | 
| MSC: | 46H70 | 
| MSC: | 46L70 | 
| idZBL: | Zbl 06321150 | 
| idMR: | MR3118865 | 
| DOI: | 10.5817/AM2013-2-79 | 
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| Date available: | 2013-10-14T13:39:04Z | 
| Last updated: | 2014-07-30 | 
| Stable URL: | http://hdl.handle.net/10338.dmlcz/143495 | 
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