Timeline for Are there other dualities on finite vector spaces besides the canonical one?
Current License: CC BY-SA 3.0
7 events
| when toggle format | what | by | license | comment | |
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| May 24, 2017 at 16:33 | comment | added | Theo Johnson-Freyd | There is a sense in which the duality is not canonical: the space of functors $F$ equipped with an isomorphism $F^2 \cong \mathrm{id}$ is not contractible. Indeed, any such functor admits a nontrivial natural automorphism, namely multiplication by $-1$. | |
| May 24, 2017 at 15:48 | vote | accept | Michael Bächtold | ||
| May 24, 2017 at 13:47 | comment | added | Arun Debray | Ah, I missed that assumption.Thank you. | |
| May 24, 2017 at 13:39 | answer | added | Chris Schommer-Pries | timeline score: 10 | |
| May 24, 2017 at 13:20 | comment | added | Chris Schommer-Pries | @ArunDebray those functors are covariant, not contravariant. | |
| May 24, 2017 at 13:17 | comment | added | Arun Debray | $F = \mathrm{id}$ satisfies those requirements, but probably isn't what you're looking for. Also, over $\mathbb{C}$, there's the complex conjugate functor, right? | |
| May 24, 2017 at 12:40 | history | asked | Michael Bächtold | CC BY-SA 3.0 |