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Timeline for Homology of infinite intersection

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Dec 25, 2015 at 14:09 history edited user9072
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Apr 17, 2014 at 23:06 comment added Włodzimierz Holsztyński Let me make the above complete. Consider the category of h-pairs $\ (X\ A).\ $ These are pairs homotopically dominated (as pairs) by finite polyhedral pairs. Then this category admits exactly one E-S homology/cohomology theory (JK suggested to me to publish it in 1970/71). Here, in this topic, we still need to narrow the class of spaces to ANR-s to get answer YES because of the behavior of the inverse limit.
Apr 17, 2014 at 22:52 comment added Włodzimierz Holsztyński Just in case, and for the sake of this topic, I'd like to stress quietly that when we talk about nice compact spaces, meaning ANR-s, then all E-S homology/cohomology theories are equivalent.
Apr 17, 2014 at 22:46 answer added Włodzimierz Holsztyński timeline score: 0
Apr 17, 2014 at 22:16 answer added Włodzimierz Holsztyński timeline score: 1
Apr 17, 2014 at 20:43 vote accept Peter Franek
Apr 17, 2014 at 16:32 answer added jacob timeline score: 3
Apr 17, 2014 at 16:26 comment added Włodzimierz Holsztyński It may be mentioned that here we talk about singular (?) homology, as opposed to Cech homology.
Apr 17, 2014 at 15:58 answer added HenrikRüping timeline score: 1
Apr 17, 2014 at 12:42 comment added Peter Franek Thanks Jacob, maybe you are right, but now I'm not completely sure what you mean by "functorial map". Do you mean that H(\cap X_i) -> H(\cap Y_i) -> lim H(Y) equals H(\cap X_i) -> lim H(X) -> lim H(Y), i.e. Milnors surjective map is a natural transformation between the "H(\cap)" and the "lim H" functors? If yes, we don't see that at the moment.
Apr 17, 2014 at 11:59 comment added jacob Perhaps I'm missing something subtle, but the map he defines is functorial, and is the inclusion-induced homomorphism for finite inverse limits. Thus, it is must also be the inclusion-induced homomorphism for infinite sequences (as you can see by truncating your sequence at fintie level).
Apr 17, 2014 at 9:41 history asked Peter Franek CC BY-SA 3.0