Timeline for Homotopy Groups of Connected Sums
Current License: CC BY-SA 3.0
12 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Aug 9, 2013 at 13:51 | comment | added | Ronnie Brown | In answer to Ryan Budney, one example in the joint paper Brown and Loday, Topology, 26 (1987), 311-334, was the calculation of the 3-type of $X= S(K(G,1))$ in terms of the nonabelian tensor square $G \otimes G$, for any group $G$. My bibliography on the nonabelian tensor product has 127 items (my name is on 7 of them), and [115] is on new calculations using GAP. Group theorists are interested because the commutator map $G \times G \to G$ is a biderivation and so factors through a morphism $\kappa:G \otimes G \to G$ whose kernel is $\pi_3 S(K(G,1))$. Abstract??!! | |
| Apr 10, 2012 at 22:30 | comment | added | Fernando Muro | "Abstract theory", hmm... are there non-abstract mathematics? Think of some elementary mathematics you think of as non-absrtract, pick an arbitrary individual in the street and ask him/her about his/her opinion... | |
| Apr 8, 2012 at 4:19 | vote | accept | Chris Gerig | ||
| Apr 6, 2012 at 20:12 | answer | added | Ronnie Brown | timeline score: 5 | |
| Apr 6, 2012 at 20:06 | answer | added | John Klein | timeline score: 10 | |
| Apr 6, 2012 at 19:31 | comment | added | Ryan Budney | I don't know of any examples of people using these higher homotopy van kampen theorems to compute anything new. But if people can point out examples that would be great. | |
| Apr 6, 2012 at 16:46 | history | edited | Chris Gerig | CC BY-SA 3.0 |
added 162 characters in body
|
| Apr 6, 2012 at 16:26 | comment | added | Chris Gerig | Sorry can this even be used in a connected-sum example? It seems just like "abstract theory". | |
| Apr 6, 2012 at 13:39 | comment | added | Fernando Muro | Higher homotopy groups, higher van Kampen theorems. | |
| Apr 6, 2012 at 7:15 | answer | added | Ryan Budney | timeline score: 34 | |
| Apr 6, 2012 at 6:47 | comment | added | Qiaochu Yuan | Perhaps ncatlab.org/nlab/show/higher+homotopy+van+Kampen+theorem ? | |
| Apr 6, 2012 at 6:23 | history | asked | Chris Gerig | CC BY-SA 3.0 |