Timeline for Automorphisms and Bicategories
Current License: CC BY-SA 3.0
7 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Oct 24, 2011 at 1:02 | vote | accept | Yuri Sulyma | ||
| Oct 23, 2011 at 4:59 | comment | added | S. Carnahan♦ | I don't have a concrete example, but I have seen papers using the groupoid language. In particular, morphisms in the Galois groupoid of $X$ are described by isomorphisms of fiber functors on the category of étale sheaves of finite sets on $X$. | |
| Oct 23, 2011 at 2:32 | comment | added | Yuri Sulyma | @JSE: Continuing the analogy, is the concept of "Galois groupoid" then useful? | |
| Oct 23, 2011 at 1:24 | answer | added | Finn Lawler | timeline score: 5 | |
| Oct 23, 2011 at 1:12 | comment | added | JSE | If this helps, you should think of the group of automorphisms of a fixed algebraic closure K as analogous to the fundamental group of a space X based at a point *. The choice of algebraic closure is the choice of basepoint. And the "Galois group" of a non-algebraically closed field is something like "the fundamental group of X" defined without reference to a basepoint -- an object that is really defined only up to conjugation. | |
| Oct 23, 2011 at 1:07 | answer | added | David Roberts♦ | timeline score: 1 | |
| Oct 22, 2011 at 23:44 | history | asked | Yuri Sulyma | CC BY-SA 3.0 |