Timeline for Cover the $n$-disc irredundantly with $n+1$ open sets. Suppose that the $(n+1)$-fold intersection is empty. Then is some $n$-fold intersection empty?
Current License: CC BY-SA 4.0
10 events
| when toggle format | what | by | license | comment | |
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| Apr 14 at 20:06 | answer | added | IJL | timeline score: 6 | |
| Apr 11 at 1:31 | history | edited | LSpice | CC BY-SA 4.0 |
Cech -> Čech, and $|\amalg|$ -> $\lvert\coprod\rvert$
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| Apr 11 at 1:22 | vote | accept | Tim Campion | ||
| Apr 11 at 1:13 | answer | added | Saúl RM | timeline score: 5 | |
| Apr 11 at 0:10 | comment | added | Saúl RM | My mistake, if we add the path the triple intersection is nonempty | |
| Apr 11 at 0:04 | comment | added | Saúl RM | Hm. I think covering of the disk by the sets $(-2,-0.5)\bigcup(0.5,2)\times\mathbb{R},(-0.9,0.5)\times\mathbb{R}$ and $(-0.5,0.9)\times\mathbb{R}$ works now? Connectedness doesn't seem to help either (you can add a small open path to connect the disconnected set) Edit: I changed some 1s to 0.9s in case we are using the open disk | |
| Apr 10 at 23:56 | comment | added | Tim Campion | @SaúlRM Thanks, I think I was missing a condition. I’ve added another condition now, but perhaps it’s still false. | |
| Apr 10 at 23:55 | history | edited | Tim Campion | CC BY-SA 4.0 |
added 111 characters in body; edited title
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| Apr 10 at 23:44 | history | edited | Tim Campion | CC BY-SA 4.0 |
added 14 characters in body
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| Apr 10 at 23:39 | history | asked | Tim Campion | CC BY-SA 4.0 |