Timeline for Homological vs. cohomological dimension of a group/space
Current License: CC BY-SA 3.0
6 events
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| Jul 15, 2015 at 6:39 | history | edited | Fernando Muro | CC BY-SA 3.0 |
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| Jul 14, 2015 at 20:56 | comment | added | Fernando Muro | Sorry, it seems that when answering Q3 I suddenly forgot that we're considering local coefficients. | |
| Jul 14, 2015 at 20:56 | history | edited | Fernando Muro | CC BY-SA 3.0 |
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| Jul 14, 2015 at 6:35 | comment | added | KotelKanim | Thanks for the answers, but I don't agree about Q3. As mark says, acyclic means trivial homology with integral coefficients. I am talking about trivial homology with any (twisted/local) coefficients. I don't think there is a non-trivial group with trivial homology as I explained in the question. | |
| Jul 14, 2015 at 5:59 | comment | added | Mark Grant | For Q3), I don't think $BG$ with $G$ acyclic is necessarily contractible. Acyclic usually means trivial homology with integer coefficients, so Higman's group is a counter-example. | |
| Jul 13, 2015 at 23:05 | history | answered | Fernando Muro | CC BY-SA 3.0 |