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Jun 24, 2015 at 18:27 vote accept user43326
Dec 10, 2013 at 16:38 answer added user43326 timeline score: 2
Dec 9, 2013 at 18:46 comment added András Bátkai You should post this as an answer.
Dec 9, 2013 at 18:00 history edited user43326 CC BY-SA 3.0
added 229 characters in body
Dec 7, 2013 at 16:18 history edited user43326 CC BY-SA 3.0
Marked as solved, with the solution.
Dec 2, 2013 at 8:48 comment added user76758 @user43326: I know almost nothing about modern homotopy theory, but I've seen other settings where a global cohomological computation encounters complications because certain signs are merely "locally constant", and so I wondered if the disconnectedness of orthogonal groups might be contributing discrepancies governed by local signs and not a single overall global sign. But this is just pure speculation, so feel free to ignore it (or maybe Oscar R-W sees something about it).
Dec 2, 2013 at 7:48 comment added user43326 @user76758: Maybe I misunderstood your comment. So basically what I am saying is that there are contradictions whatever the choice of signs are, which are only "locally constant".
Nov 30, 2013 at 6:58 history edited user43326 CC BY-SA 3.0
Added a second argument showing $2id\neq 2Switch$.
Nov 28, 2013 at 11:16 comment added user43326 @OscarRandal-Williams I edited the question, added a paragraph explaining why $2\tau \neq 2⋅Id$.
Nov 28, 2013 at 11:05 history edited user43326 CC BY-SA 3.0
Removed the markar [Solved], added the reason why $2(id-Switch)$ is non-null
Nov 28, 2013 at 10:34 history edited user43326 CC BY-SA 3.0
Marked as solved
Nov 27, 2013 at 17:09 comment added Oscar Randal-Williams The issue would be resolved if $Id - \tau = \tau - Id$ (so $2\tau = 2\cdot Id$), where $\tau$ is the switch map. I suspect that this is true, but I don't see an independent way to prove it.
Nov 26, 2013 at 20:37 comment added user43326 @user76758 The connectedness of the group is irrelevant, we have the double coset formula for discrete groups as well. Besides, the classifying space is connected.
Nov 26, 2013 at 20:00 review First posts
Nov 26, 2013 at 20:00
Nov 26, 2013 at 20:00 comment added user76758 How do you know that you have "globally constant" signs when working with a disconnected group?
Nov 26, 2013 at 19:43 history asked user43326 CC BY-SA 3.0