| Title: | Copies of $l_{p}^{n}$'s uniformly in the spaces $\Pi _{2}( C[ 0,1] ,X) $ and $\Pi _{1}(C[ 0,1],X) $ (English) | 
| Author: | Popa, Dumitru | 
| Language: | English | 
| Journal: | Czechoslovak Mathematical Journal | 
| ISSN: | 0011-4642 (print) | 
| ISSN: | 1572-9141 (online) | 
| Volume: | 67 | 
| Issue: | 2 | 
| Year: | 2017 | 
| Pages: | 457-467 | 
| Summary lang: | English | 
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| Category: | math | 
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| Summary: | We study the presence of copies of $l_{p}^{n}$'s uniformly in the spaces $\Pi _{2}( C[ 0,1] ,X) $ and $\Pi _{1}( C[0,1] ,X)$. By using Dvoretzky's theorem we deduce that if $X$ is an infinite-dimensional Banach space, then $\Pi _{2}( C[ 0,1] ,X) $ contains $\lambda \sqrt {2}$-uniformly copies of $l_{\infty }^{n}$'s and $\Pi _{1}( C[ 0,1] ,X) $ contains $\lambda $-uniformly copies of $l_{2}^{n}$'s for all $\lambda >1$. As an application, we show that if $X$ is an infinite-dimensional Banach space then the spaces $\Pi _{2}( C[ 0,1] ,X) $ and $\Pi _{1}( C[ 0,1] ,X) $ are distinct, extending the well-known result that the spaces $\Pi _{2}( C[ 0,1],X) $ and $\mathcal {N}( C[ 0,1] ,X) $ are distinct. (English) | 
| Keyword: | $p$-summing linear operators | 
| Keyword: | copies of $l_{p}^{n}$'s uniformly | 
| Keyword: | local structure of a Banach space | 
| Keyword: | multiplication operator | 
| Keyword: | average | 
| MSC: | 46B07 | 
| MSC: | 46B28 | 
| MSC: | 47B10 | 
| MSC: | 47L20 | 
| idZBL: | Zbl 06738531 | 
| idMR: | MR3661053 | 
| DOI: | 10.21136/CMJ.2017.0009-16 | 
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| Date available: | 2017-06-01T14:30:05Z | 
| Last updated: | 2020-07-03 | 
| Stable URL: | http://hdl.handle.net/10338.dmlcz/146768 | 
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