Infinitesimally Central Extensions of Chevalley Groups

Conventions....Pages 1-1
Universal central extensions. Central trick....Pages 2-5
Degenerate sums. The extension r : $$\underset{\raise0.3em\hbox{$\smash{\scriptscriptstyle-}$}}{g} '\mathbb{Z} \to \underset{\raise0.3em\hbox{$\smash{\scriptscriptstyle-}$}}{g} \mathbb{Z}$$ ....Pages 5-22
The action Âd. Structure of g* Z , g* R ....Pages 22-38
Admissible lattices and the category L V . Σ-connected components....Pages 39-46
The G-module ker π....Pages 46-51
G-invariant [p]-structures....Pages 51-54
The extension φ : G* → G....Pages 54-59
Extensions of G by a G-module....Pages 59-61
The hochschild groups....Pages 61-65
The existence of φ : G* → G....Pages 65-97
Relations in the open cell....Pages 97-118
Representatives in G* of the Weyl group....Pages 119-124
The theorem of generators and relations and its consequences....Pages 124-138
The group functor G*....Pages 138-140