Abstract:
We study the Ricci curvature of completely solvable metric Lie algebras. In particular, we prove that the Ricci operator of every completely solvable nonunimodular or every noncommutative nilpotent metric Lie algebra has at least two negative eigenvalues.
Key words:nonhomogeneous Riemannian manifolds, Lie group and algebras, completely solvable Lie algebras, left-invariant Riemannian metrics, Ricci curvature.