Timeline for Is there a functorial proof that Eilenberg-MacLane spaces are unique up to homotopy equivalence?
Current License: CC BY-SA 2.5
4 events
| when toggle format | what | by | license | comment | |
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| Oct 14, 2011 at 15:31 | comment | added | Tom Church | Dear Ilya, you're completely correct. That's a good thing to point out explicitly. Thanks! | |
| Oct 14, 2011 at 6:08 | comment | added | Ilya Grigoriev | Hi, Tom! Your answer confused me a bit. I think it's important to point out that for $n>1$, the correct version of Proposition 1B.9 is that for any (n-1)-connected CW complex X, the maps on $\pi_n$ are indueced by maps $X \to K(G,n)$. In this case, the maps on $\pi_n$ are basically the same as $n$-th cohomology of $X$. If you don't say "$(n-1)$-connected", the statement is wrong. For example, take $n=3$ and $X=S^2$. | |
| Dec 11, 2010 at 5:09 | vote | accept | Akhil Mathew | ||
| Dec 10, 2010 at 6:06 | history | answered | Tom Church | CC BY-SA 2.5 |