Timeline for Existence of weird complex norms
Current License: CC BY-SA 4.0
8 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Feb 13, 2023 at 21:23 | history | became hot network question | |||
| Feb 13, 2023 at 16:11 | vote | accept | Benoit Gaudeul | ||
| Feb 13, 2023 at 15:46 | comment | added | Willie Wong | I just learned (from Wikipedia), that the subordinate norm is another word for operator norm. Which also explains the answer below. | |
| Feb 13, 2023 at 14:59 | answer | added | Christophe Leuridan | timeline score: 6 | |
| Feb 13, 2023 at 14:50 | comment | added | Yemon Choi | If $\Vert\cdot\Vert_2$ denotes the usual norm on ${\bf C}^2$ and we pick an invertible $A\in {\rm GL}_2({\mathbb C})$ then we can define a new norm by $\Vert x\Vert_A = \Vert Ax\Vert_2$. I suspect, but have not checked, that "most" choices of $A$ will lead to examples where there exist $y\in {\bf C}^2$ such that $\Vert Dy\Vert_A > \Vert y\Vert$. | |
| Feb 13, 2023 at 13:44 | history | edited | YCor |
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| S Feb 13, 2023 at 13:12 | review | First questions | |||
| Feb 13, 2023 at 15:50 | |||||
| S Feb 13, 2023 at 13:12 | history | asked | Benoit Gaudeul | CC BY-SA 4.0 |