Timeline for Closed subsets in Coxeter groups
Current License: CC BY-SA 4.0
5 events
| when toggle format | what | by | license | comment | |
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| Oct 27, 2018 at 17:31 | comment | added | Jim Humphreys | @YCor: The question does seem more natural when posed for 'root systems' if defined in a suitable way; but Deodhar's notion of such a root system for an arbitrary Coxeter group is even more reasonable here: for example, in the finite BC situation, the use of unit vectors as roots solves the problem here. (See Deodhar's paper or my 1990 book on reflection groups for more details.) On the other hand, I'm not convinced that this question is really at research-level. | |
| Oct 27, 2018 at 16:15 | review | Close votes | |||
| Nov 11, 2018 at 3:05 | |||||
| Oct 27, 2018 at 13:08 | comment | added | YCor | How do you define roots of a Coxeter group (associated to a Coxeter system)? the Coxeter group is the same for $B_n$ and $C_n$, $n\ge 3$, while the root system are not the same. Isn't the question natural to ask simply starting with a root system? | |
| Oct 27, 2018 at 12:39 | answer | added | Philipp Lampe | timeline score: 3 | |
| Oct 27, 2018 at 11:58 | history | asked | Jianrong Li | CC BY-SA 4.0 |