Timeline for Examples of common false beliefs in mathematics
Current License: CC BY-SA 4.0
5 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Oct 16, 2020 at 11:39 | comment | added | Louis Hainaut | I think the best example where this constitutes a mistake is the category of rings. For example the inclusion $\mathbb{Z}\to \mathbb{Q}$ is an epimorphism. | |
| Sep 16, 2020 at 13:00 | comment | added | Amos Kaminski | If you mean set theoretic surjective then in every concrete category a morphism is surjective then the morphism is epi and in all the category that I know epi are something very reasonable for example in Hausdorff spaces epi are exactly the map with dense image ... | |
| Apr 25, 2020 at 13:15 | comment | added | Willie Wong | Can you give a concrete example why it is a "mistake"? | |
| S Apr 25, 2020 at 0:06 | history | answered | user147204 | CC BY-SA 4.0 | |
| S Apr 25, 2020 at 0:06 | history | made wiki | Post Made Community Wiki by user147204 |