Extensions of simple modules for the Witt algebra

الأصل · EN

The irreducible representations of the Witt algebra W are completely known. A classification of the irreducible Uχ(W)--modules was first established by Chang and later simplified by Strade. The aim of this article is to give a classification of the extensions of the simple Uχ(W)--modules having p--character χ of height -1,0,1 and p-1 where p denotes the characteristic of the ground field.