Timeline for Two pullback diagram
Current License: CC BY-SA 3.0
4 events
| when toggle format | what | by | license | comment | |
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| Sep 26, 2013 at 21:04 | comment | added | Zhen Lin | Ah, right. I forgot that regular epimorphisms are effective epimorphisms when kernel pairs exist. Thanks! | |
| Sep 26, 2013 at 21:01 | comment | added | john | Consider a category with pullbacks and a topology on it in which all covers consists of single arrows. Then all representables are sheaves if and only if all covers are the coequalisers of their kernel pairs. | |
| Sep 26, 2013 at 20:53 | comment | added | Zhen Lin | Wonderful heuristic! But can you say more about why the topology we get is subcanonical? | |
| Sep 26, 2013 at 20:25 | history | answered | john | CC BY-SA 3.0 |