Timeline for Find $Y\in\operatorname{GL}_n(\mathbb{Z})$ such that all eigenvalues of $YX$ are nonnegative
Current License: CC BY-SA 4.0
17 events
| when toggle format | what | by | license | comment | |
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| Feb 6 at 20:37 | history | edited | LSpice | CC BY-SA 4.0 |
`\mathrm` -> `\operatorname`, while this is on the front page
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| Feb 6 at 17:23 | answer | added | loup blanc | timeline score: 1 | |
| Feb 3 at 15:06 | history | edited | YCor | CC BY-SA 4.0 |
made title more precise, added tags
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| Feb 3 at 12:54 | comment | added | Nathaniel Johnston | For the first question (where $X \in M_n(\mathbb{R})$), this seems straightforward if $X$ has rational entries: pick $Y$ so that $YX$ is a positive multiple of the reduced row echelon form of $X$, which is triangular and has all diagonal entries (i.e., eigenvalues) equal to $0$ or some positive integer. | |
| Feb 2 at 22:07 | history | bumped | CommunityBot | This question has answers that may be good or bad; the system has marked it active so that they can be reviewed. | |
| Oct 5, 2023 at 21:07 | history | bumped | CommunityBot | This question has answers that may be good or bad; the system has marked it active so that they can be reviewed. | |
| Jun 7, 2023 at 19:03 | history | bumped | CommunityBot | This question has answers that may be good or bad; the system has marked it active so that they can be reviewed. | |
| Feb 7, 2023 at 18:50 | review | Close votes | |||
| Feb 9, 2023 at 9:41 | |||||
| Feb 7, 2023 at 18:47 | comment | added | David E Speyer | @RyanBudney Can you do the problem? It doesn't seem at all easy to me, which makes me doubt that it is a homework problem. | |
| Feb 7, 2023 at 18:32 | comment | added | Ryan Budney | Is this a homework problem? It looks like the kind of problem you give students when they learn about row or column echelon form. | |
| Feb 7, 2023 at 18:05 | history | bumped | CommunityBot | This question has answers that may be good or bad; the system has marked it active so that they can be reviewed. | |
| Oct 10, 2022 at 18:05 | history | bumped | CommunityBot | This question has answers that may be good or bad; the system has marked it active so that they can be reviewed. | |
| Jun 12, 2022 at 17:07 | history | bumped | CommunityBot | This question has answers that may be good or bad; the system has marked it active so that they can be reviewed. | |
| Apr 27, 2022 at 9:25 | answer | added | Derek | timeline score: 0 | |
| Apr 9, 2022 at 13:52 | history | edited | jack | CC BY-SA 4.0 |
added 34 characters in body
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| Apr 9, 2022 at 13:40 | comment | added | Wojowu | Do you want $Y$ invertible over $\mathbb Z$ or over $\mathbb R$/$\mathbb C$? I'm not sure that makes a difference but it might be good to clarify things. | |
| Apr 9, 2022 at 13:31 | history | asked | jack | CC BY-SA 4.0 |