# What is there in the book Cohomologie non abélienne by Jean Giraud

These days I am trying to understand about stacks and gerbes.

Most of the articles that has something to do with gerbes cite this work Cohomologie non abélienne by Jean Giraud.

I do not read the language it is written in and I could not see an English translation for the same.

It would definitely give some motivation to know what is there in this master’s work. I am not asking to summarise 400 pages work in an answer. Some information about outline of a particular topic would be useful(I am not sure if it is even possible).

• As there is no single answer, do we have to make it community wiki?? – Praphulla Koushik Mar 29 '18 at 13:17
• I would recommend making the problem community wiki. – Ben McKay Mar 29 '18 at 13:36
• Giraud develops a theory of nonabelian cohomology in a very general setting. His $H^2$ classifies the gerbes bound by a given band (lien). It is written in the style of EGA, which many of us find unattractive. There is a 4 page summary in the appendix to Tannakian Categories by Deligne and Milne. jmilne.org/math/xnotes/tc.html – anon Mar 29 '18 at 17:30
• If you have access to MathSciNet, look up the work (searching e. g. by author or title). The review looks like a good place to start; the number is MR0344253. – Margaret Friedland Mar 29 '18 at 19:23
• @MargaretFriedland that is a good choice I believe. Right now I am in my home(where I don’t have access to Math sci net), I go to institute on Monday. I will see that then. Thanks. – Praphulla Koushik Mar 29 '18 at 20:02