Cohomology and homotopy
In higher category theory
The notion of Galois topos formalizes the collection of locally constant sheaves that are classified by Galois theory in the connected and locally connected case.
be a topos sitting by its global section geometric morphism over a base .
For an object in , let be its automorphism group (in ). Then is canonically a group object in .
An inhabited object (the terminal morphism is an epimorphism) in is called a Galois object if it is a -torsor/principal bundle in , in that the canonical morphism
is an isomorphism.
A Galois topos is a topos that is
This appears as (Dubuc, theorem 5.2.4).
The definition appears in
Revised on March 18, 2013 03:12:05
by Bas Spitters