Timeline for Nilpotent orbits and subspaces
Current License: CC BY-SA 3.0
4 events
| when toggle format | what | by | license | comment | |
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| May 18, 2015 at 16:28 | comment | added | Daniel Juteau | @AllenKnutson If $(x,h,y)$ is an $SL_2$-triple where $x$ is the given nilpotent orbit, then $h$ defines a grading on the Lie algebra. The orbit is even if the grading is even. One can chose a dominant $h$, and then the weights of simple roots are in $\{0,1,2\}$, this gives a labelling of the Dynkin diagram which is characteristic of the orbit. Even means there are no 1's. | |
| May 18, 2015 at 11:17 | comment | added | Allen Knutson | What does "$X$ is even" mean? It's always even-dimensional, so I presume that's not what you mean. | |
| May 17, 2015 at 10:50 | comment | added | Ben Webster♦ | @PeterMichor they are "cones" but in the complex sense, so closed under multiplication by any complex number. Think about Jordan normal form; for any classical group, that determines the nilpotent. | |
| May 16, 2015 at 23:04 | history | asked | Bugs Bunny | CC BY-SA 3.0 |