Some properties of the space of n-dimensional Lie algebras

摘要

Some general properties of the space of n-dimensional Lie algebras are studied. This space is defined by the system of Jacobi's quadratic equations. It is proved that these equations are linearly independent and equivalent to each other (more precisely, the quadratic forms defining these equations are affinely equivalent). Moreover, the problem on the closures of some orbits of the natural action of the group on is considered. Two Lie algebras are indicated whose orbits are closed in the projectivization of the space. The intersection of all irreducible components of the space is also treated. It is proved that this intersection is nontrivial and consists of nilpotent Lie algebras. Two Lie algebras belonging to this intersection are indicated. Some other results concerning arbitrary Lie algebras and the space formed by these algebras are presented. Bibliography: 17 titles.