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Timeline for Why the Dold-Thom theorem?

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Mar 7, 2016 at 20:14 comment added მამუკა ჯიბლაძე @lenticcatachresis Just a minor issue with basepoints, nothing serious.
Mar 7, 2016 at 15:37 comment added Bruno Stonek @მამუკაჯიბლაძე: why is SP(X) only a free commutative topological monoid "of sorts"? Why the "of sorts"?
Oct 23, 2014 at 19:07 vote accept Chris Gerig
Oct 15, 2014 at 2:37 comment added Dev Sinha For intuition, I think a key is the first case of X a sphere. If one uses the model of a cube relative to its boundary, then the free abelian group on X is essentially the iterated bar construction, and so a model for an Eilenberg-MacClane space.
Oct 8, 2014 at 7:20 answer added Qiaochu Yuan timeline score: 15
Oct 8, 2014 at 5:32 answer added მამუკა ჯიბლაძე timeline score: 18
Oct 7, 2014 at 22:38 history edited Chris Gerig CC BY-SA 3.0
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Oct 7, 2014 at 22:12 answer added Ryan Budney timeline score: 9
Oct 7, 2014 at 19:47 comment added მამუკა ჯიბლაძე @BenWieland yes, I agree. On the other hand I only mentioned the simplicial context as a sort of analogy, although it is also true that one might switch to it via, say, singular simplices and then relate Sing(SP(X)) to Z[Sing(X)]...
Oct 7, 2014 at 19:27 comment added Ben Wieland @მამუკა ჯიბლაძე, I agree that is the right perspective, but you need a little bit more. $\mathbb Z[X]$ is a simplicial abelian group. There are two things you can do with it: turn it into a chain complex and take homology; or turn it into a space and take homotopy groups. You need to know that they correspond. This is sometimes included in Dold-Kan.
Oct 7, 2014 at 19:09 answer added Jesse C. McKeown timeline score: 9
Oct 7, 2014 at 17:53 comment added მამუკა ჯიბლაძე Sort of intuitive heuristics behind the fact (for me) is that (a) SP(X) is the free commutative topological monoid on X (of sorts); (b) connected topological monoids possess homotopy inverses, so it is actually free topological abelian group on X (again sort of); (c) homology of X is more or less the same as homotopy of the free topological abelian group on X. All this is almost rigorous in the simplicial context, where $\tilde H_*(X)=\pi_*\mathbb Z[X]$, more or less by definition.
Oct 7, 2014 at 17:48 history asked Chris Gerig CC BY-SA 3.0