Timeline for Negative property in category [closed]
Current License: CC BY-SA 3.0
7 events
| when toggle format | what | by | license | comment | |
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| Aug 5, 2011 at 22:54 | history | closed |
Dan Petersen D.-C. Cisinski Ryan Budney Martin Brandenburg Tom Leinster |
not a real question | |
| Aug 5, 2011 at 22:54 | comment | added | Tom Leinster | Strahinja, I'm voting to close. It sounds as if you're just getting to grips with the basic ideas of category theory, which is an excellent thing to be doing, but probably means that it would be more appropriate to post your questions at math.stackexchange.com. (They'd also probably appreciate it if your questions were more focused than this one. Specific questions are good.) | |
| Aug 2, 2011 at 17:42 | comment | added | Ryan Budney | Another technique is to show that the automorphism group of an object in a category isn't isomorphic to the automorphism group of any object in the other category. | |
| Aug 1, 2011 at 20:31 | comment | added | Strahinja Popovic | How could I prove that two type systems are of different expressive power, using just category theory? Probably the easiest example would be of untyped and simply typed lambda calculus. | |
| Aug 1, 2011 at 20:25 | comment | added | Andrej Bauer | Give us an example of what you want to do. But in general it's about invariants, as Qiaochu says. | |
| Aug 1, 2011 at 20:10 | comment | added | Qiaochu Yuan | Categories have lots of invariants. For example, whether various types of limits or colimits exist in them. The homotopy type of their nerves... | |
| Aug 1, 2011 at 20:06 | history | asked | Strahinja Popovic | CC BY-SA 3.0 |