Published Paper
Inserted: 24 may 2018
Last Updated: 18 may 2025
Journal: Forum Math.
Volume: 32
Number: 6
Pages: 1599–1619
Year: 2020
Doi: https://doi.org/10.1515/forum-2020-0049
Abstract:
We introduce a systematic method to produce left-invariant, non-Ricci-flat Einstein metrics of indefinite signature on nice nilpotent Lie groups. On a nice nilpotent Lie group, we give a simple algebraic characterization of non-Ricci-flat left-invariant Einstein metrics in both the class of metrics for which the nice basis is orthogonal and a more general class associated to order two permutations of the nice basis. We obtain classifications in dimension 8 and, under the assumption that the root matrix is surjective, dimension 9; moreover, we prove that Einstein nilpotent Lie groups of nonzero scalar curvature exist in every dimension $\geq 8$.