Timeline for Examples where existence is harder than evaluation
Current License: CC BY-SA 4.0
6 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| May 17, 2019 at 15:06 | comment | added | David E Speyer | @schematic_boi I think the theorem is "a simple group which has an involution whose centralizer is a certain double cover of Fischer's Baby Monster group must have the following character table" (and, in particular, the stated order). | |
| May 10, 2019 at 14:17 | comment | added | user138661 | the comment was not meant to be hostile of course, more to clarify. I mean, if there is no exact theorem then it is not clear (to me, at least) what expression are we evaluating. The order of some group some guy decided to call "the Monster"? Does not sound very explicit. But maybe my ignorance of finite group theory is showing here. | |
| May 10, 2019 at 12:44 | comment | added | Gerry Myerson | The original question is, "What are some interesting examples where evaluating an expression assuming its existence is much easier than proving existence?" so there's no request for an "exact theorem" there. The order of the group, and its character table, were evaluated before it was proved to exist. But maybe I'm missing the point of your comment. | |
| May 10, 2019 at 7:36 | comment | added | user138661 | but what is the exact theorem, like "A group with such and such properties (which may or may not exist) has order $N$"? | |
| S May 8, 2019 at 23:54 | history | answered | Gerry Myerson | CC BY-SA 4.0 | |
| S May 8, 2019 at 23:54 | history | made wiki | Post Made Community Wiki by Gerry Myerson |