Timeline for Extending coverings over dense subsets
Current License: CC BY-SA 3.0
6 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Jun 25, 2013 at 3:02 | review | First posts | |||
| Jun 25, 2013 at 15:43 | |||||
| Jun 20, 2013 at 8:03 | history | edited | Neil Strickland | CC BY-SA 3.0 |
Spelling in title
|
| Jun 20, 2013 at 7:48 | comment | added | Robert Israel | Diameters really have very little to do with it. Given any covering of $D$ that misses a point $p$ of $X$, and any set $S$ of diameter $d$ disjoint from $p$, you can take the unions of the members of the covering with $S$ and get a new covering whose elements all have diameter $\ge d$, but it still misses $p$. | |
| Jun 20, 2013 at 6:30 | comment | added | Anton Petrunin | If the diameters bounded below, the cvering of D might not cover X. For example, let X be the real line. D be the set of rational numbers and it is covered by two sets $(-\infty,\sqrt{2})$ and $(\sqrt{2},+\infty)$. | |
| Jun 20, 2013 at 6:06 | comment | added | Zev Chonoles | Crossposted from math.SE: math.stackexchange.com/q/425179/264 | |
| Jun 20, 2013 at 5:57 | history | asked | Michael | CC BY-SA 3.0 |