Timeline for Action of certain endomorphisms on Pontriyagin dual
Current License: CC BY-SA 3.0
13 events
| when toggle format | what | by | license | comment | |
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| Oct 11, 2016 at 2:20 | vote | accept | rohitna | ||
| Oct 10, 2016 at 18:04 | answer | added | Frieder Ladisch | timeline score: 4 | |
| Oct 9, 2016 at 19:58 | vote | accept | rohitna | ||
| Oct 11, 2016 at 2:20 | |||||
| Oct 9, 2016 at 19:40 | history | edited | rohitna | CC BY-SA 3.0 |
added 587 characters in body
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| Oct 9, 2016 at 19:34 | comment | added | rohitna | You are right. I'll just edit my question and add the above as a motivation. | |
| Oct 9, 2016 at 19:23 | comment | added | Uri Bader | My previous comment was harsh, but too many questions on this site are not well motivated. There are $\aleph_0$ many arbitrary questions, and a great deal of those appear here. I see now that yours is indeed motivated. It will be useful (for you, first of all) if next time you put a question you will try to explain its importance in the first place. | |
| Oct 9, 2016 at 18:53 | comment | added | rohitna | A reference is James's book on representations of general linear group. | |
| Oct 9, 2016 at 18:52 | comment | added | rohitna | This appears naturally when we study representation theory of unipotent groups. Suppose $U$ be the subgroup of unipotent lower triangular matrices in $GL_n(R)$. Then elements of the form $E_{\chi} = \sum_{M \in U} \chi(M_{2,1}) M \in F[U]$ appear naturally where $\chi$ is an $F$-valued character. There is nothing special about $M_{2,1}$, one can work with any closed "root subgroup". Now conjugating $E_{\chi}$ by an element of the cartan subgroup yields $E_{\chi(.b)}$ for some $b$ and so it becomes useful to know whether all characters can be obtained in this way. | |
| Oct 9, 2016 at 13:01 | comment | added | Uri Bader | I put an answer below, but I must say that now I regret it. The question seems entirely random and unmotivated. | |
| Oct 9, 2016 at 11:59 | answer | added | Uri Bader | timeline score: 2 | |
| Oct 9, 2016 at 4:34 | history | edited | rohitna | CC BY-SA 3.0 |
edited body
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| Oct 9, 2016 at 4:23 | review | First posts | |||
| Oct 9, 2016 at 4:47 | |||||
| Oct 9, 2016 at 4:10 | history | asked | rohitna | CC BY-SA 3.0 |