2-Cohomology Groups And Automorphism Groups Of Several Nilpotent Lie Algebras

2-Cohomology and automorphism of nilpotent Lie algebras play important roles.In this paper,we mainly studied 2-cohomology groups and automorphism groups of several nilpotent Lie algebras.In the first section,using the definition of a 2-cohomology groups,we calculate the dimension of 2-cohomology groups of Qn,Wn and two step nilpotent Lie algebras of dimension 8.In the second sec-tion,according to the definition of Lie algebra automorphism groups,we describe the matrix form of Ln,Qn automorphism groups.Then using the minimal faithful representation of Qn,we characterize some subgroups of automorphism groups of Qn,including inner automorphism groups,central automorphism groups,involution automorphism groups and outer automorphism groups.