Timeline for Classification of weak 3-groups
Current License: CC BY-SA 3.0
8 events
| when toggle format | what | by | license | comment | |
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| Jun 11, 2017 at 1:49 | history | edited | Qiaochu Yuan | CC BY-SA 3.0 |
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| Jun 10, 2017 at 22:37 | comment | added | Xiao-Gang Wen | @Qiaochu Yuan Thank you for the answer. What is $H^4(B^2 \pi_2, \pi_3)$ when $\pi_3=U(1)$ and $\pi_2=Z_2$? | |
| Jun 10, 2017 at 19:38 | comment | added | Alexander Chervov | Ah, sorry, I misunderstood the question. | |
| Jun 10, 2017 at 19:24 | comment | added | Qiaochu Yuan | @Alexander: no, the question is about 3-groups, or equivalently about pointed connected spaces $X$ with only $\pi_1(X), \pi_2(X), \pi_3(X)$ nontrivial. These can be understood as being built from "extensions" but of Eilenberg-MacLane spaces, not groups. | |
| Jun 10, 2017 at 19:15 | comment | added | Alexander Chervov | Not a critics, just to understand - as far as i understand question was about group which is which is made by extensions from 3 abelian groups, or I misunderstand something ? if so where how all that looping-delooping is related ? | |
| Jun 10, 2017 at 18:00 | history | edited | Qiaochu Yuan | CC BY-SA 3.0 |
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| Jun 10, 2017 at 17:51 | history | edited | Qiaochu Yuan | CC BY-SA 3.0 |
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| Jun 10, 2017 at 16:17 | history | answered | Qiaochu Yuan | CC BY-SA 3.0 |