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Timeline for From Weyl groups to Weyl groupoids?

Current License: CC BY-SA 3.0

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May 1, 2016 at 20:36 vote accept Saal Hardali
Apr 30, 2016 at 19:29 vote accept Saal Hardali
May 1, 2016 at 16:28
Apr 30, 2016 at 19:17 answer added Ben Webster timeline score: 6
Apr 30, 2016 at 18:20 answer added Uri Bader timeline score: 4
Apr 30, 2016 at 16:00 comment added Saal Hardali @S.Carnahan That's great! Can I make this geometric? i.e. is there a weyl group torsor $W \to G/B \to G/T$ ?
Apr 30, 2016 at 15:54 comment added S. Carnahan I would normally choose morphisms to be automorphisms seen as elements of $GL(\mathfrak{g})$ instead of exponentials - this is not a big deal as long as you work over the real or complex numbers. To get a Weyl group, you consider a groupoid whose objects are Cartan subalgebras, together with the obvious functor from $\mathcal{W}$. Fibers are naturally W-torsors.
Apr 30, 2016 at 15:54 comment added Qiaochu Yuan It's easier to have this discussion on the Lie group rather than Lie algebra level. There for $G$ a compact connected Lie group you can consider the groupoid whose objects are maximal tori and whose morphisms are conjugations. Every object in this groupoid is isomorphic, and all of their automorphism groups are the Weyl group.
Apr 30, 2016 at 13:13 history edited Saal Hardali
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Apr 30, 2016 at 13:06 history asked Saal Hardali CC BY-SA 3.0