| Title:
|
Ultracompanions of subsets of a group (English) |
| Author:
|
Protasov, I. |
| Author:
|
Slobodianiuk, S. |
| Language:
|
English |
| Journal:
|
Commentationes Mathematicae Universitatis Carolinae |
| ISSN:
|
0010-2628 (print) |
| ISSN:
|
1213-7243 (online) |
| Volume:
|
55 |
| Issue:
|
2 |
| Year:
|
2014 |
| Pages:
|
257-265 |
| Summary lang:
|
English |
| . |
| Category:
|
math |
| . |
| Summary:
|
Let $G$ be a group, $\beta G$ be the Stone-Čech compactification of $G$ endowed with the structure of a right topological semigroup and $G^*=\beta G\setminus G$. Given any subset $A$ of $G$ and $p\in G^*$, we define the $p$-companion $\Delta _p(A)= A^*\cap Gp$ of $A$, and characterize the subsets with finite and discrete ultracompanions. (English) |
| Keyword:
|
Stone-Čech compactification |
| Keyword:
|
ultracompanion |
| Keyword:
|
sparse and discrete subsets of a group |
| MSC:
|
20F69 |
| MSC:
|
22A15 |
| MSC:
|
54D35 |
| idZBL:
|
Zbl 06391542 |
| idMR:
|
MR3193930 |
| . |
| Date available:
|
2014-06-07T15:43:00Z |
| Last updated:
|
2016-07-01 |
| Stable URL:
|
http://hdl.handle.net/10338.dmlcz/143806 |
| . |
| Reference:
|
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| Reference:
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| Reference:
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| Reference:
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| Reference:
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| . |
