Timeline for Kan extensions and the yoneda embedding.
Current License: CC BY-SA 3.0
2 events
| when toggle format | what | by | license | comment | |
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| Nov 21, 2013 at 17:54 | comment | added | Gerrit Begher | Interesting: $f_!(\{x\})$ is allways the complement of the image $f(X)$ except when $x$ is the only element in the respective fiber of $f$. So in general $f_!$ should maybe say something about the triviality of fibers. Let's see where this leads for general quasiorders aka 2-enriched categories. Here $\{x\}$ needs to be replaced with the respective down-set. | |
| Nov 21, 2013 at 12:05 | history | answered | Fujita Tomomi | CC BY-SA 3.0 |