| Title: | $C(X)$ can sometimes determine $X$ without $X$ being realcompact (English) | 
| Author: | Henriksen, Melvin | 
| Author: | Mitra, Biswajit | 
| Language: | English | 
| Journal: | Commentationes Mathematicae Universitatis Carolinae | 
| ISSN: | 0010-2628 (print) | 
| ISSN: | 1213-7243 (online) | 
| Volume: | 46 | 
| Issue: | 4 | 
| Year: | 2005 | 
| Pages: | 711-720 | 
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| Category: | math | 
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| Summary: | As usual $C(X)$ will denote the ring of real-valued continuous functions on a Tychonoff space $X$. It is well-known that if $X$ and $Y$ are realcompact spaces such that $C(X)$ and $C(Y)$ are isomorphic, then $X$ and $Y$ are homeomorphic; that is $C(X)$ {\it determines\/} $X$. The restriction to realcompact spaces stems from the fact that $C(X)$ and $C(\upsilon X)$ are isomorphic, where $\upsilon X$ is the (Hewitt) realcompactification of $X$. In this note, a class of locally compact spaces $X$ that includes properly the class of locally compact realcompact spaces is exhibited such that $C(X)$ determines $X$. The problem of getting similar results for other restricted classes of generalized realcompact spaces is posed. (English) | 
| Keyword: | nearly realcompact space | 
| Keyword: | fast set | 
| Keyword: | SRM ideal | 
| Keyword: | continuous functions with pseudocompact support | 
| Keyword: | locally compact | 
| Keyword: | locally pseudocompact | 
| MSC: | 46E25 | 
| MSC: | 54C35 | 
| MSC: | 54C40 | 
| idZBL: | Zbl 1121.54035 | 
| idMR: | MR2259501 | 
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| Date available: | 2009-05-05T16:54:32Z | 
| Last updated: | 2012-04-30 | 
| Stable URL: | http://hdl.handle.net/10338.dmlcz/119561 | 
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