| Title:
|
On $\pi$-caliber and an application of Prikry's partial order (English) |
| Author:
|
Szymanski, Andrzej |
| Language:
|
English |
| Journal:
|
Commentationes Mathematicae Universitatis Carolinae |
| ISSN:
|
0010-2628 (print) |
| ISSN:
|
1213-7243 (online) |
| Volume:
|
52 |
| Issue:
|
3 |
| Year:
|
2011 |
| Pages:
|
463-471 |
| Summary lang:
|
English |
| . |
| Category:
|
math |
| . |
| Summary:
|
We study the concept of $\pi$-caliber as an alternative to the well known concept of caliber. $\pi$-caliber and caliber values coincide for regular cardinals greater than or equal to the Souslin number of a space. Unlike caliber, $\pi$-caliber may take on values below the Souslin number of a space. Under Martin's axiom, $2^{\omega }$ is a $\pi$-caliber of $\mathbb{N}^{\ast}$. Prikry's poset is used to settle a problem by Fedeli regarding possible values of very weak caliber. (English) |
| Keyword:
|
nowhere dense |
| Keyword:
|
point-$\kappa $ family |
| Keyword:
|
$\pi $-caliber |
| MSC:
|
03E35 |
| MSC:
|
54A15 |
| MSC:
|
54A38 |
| idZBL:
|
Zbl 1249.54011 |
| idMR:
|
MR2843237 |
| . |
| Date available:
|
2011-08-15T19:28:45Z |
| Last updated:
|
2013-10-14 |
| Stable URL:
|
http://hdl.handle.net/10338.dmlcz/141616 |
| . |
| Reference:
|
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| . |
