On Einstein Extensions of Nilpotent Metric Lie Algebras
Matematičeskie trudy, Tome 10 (2007) no. 1, pp. 164-190.

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The main result of the article is as follows: If a nilpotent noncommutative metric Lie algebra $(\mathfrak n,Q)$ is such that the operator $\operatorname{Id}-\frac{\operatorname{trace}(\mathrm{Ric})}{\operatorname{trace}(\mathrm{Ric}^2)}\mathrm{Ric}$ is positive definite then every Einstein solvable extension of $(\mathfrak n,Q)$ is standard. We deduce several consequences of this assertion. In particular, we prove that all Einstein solvmanifolds of dimension at most 7 are standard.
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Yu. G. Nikonorov. On Einstein Extensions of Nilpotent Metric Lie Algebras. Matematičeskie trudy, Tome 10 (2007) no. 1, pp. 164-190. http://geodesic.mathdoc.fr/item/MT_2007_10_1_a7/

[1] Alekseevskii D. V., “Sopryazhennost polyarnykh razlozhenii grupp Li”, Mat. sb., 84 (1971), 14–26 | MR | Zbl

[2] Alekseevskii D. V., “Odnorodnye rimanovy prostranstva otritsatelnoi krivizny”, Mat. sb., 96 (1975), 93–117 | MR | Zbl

[3] Besse A. L., Mnogoobraziya Einshteina, Mir, M., 1990 | MR | Zbl

[4] Vinberg E. B., Gorbatsevich V. V., Onischik A. L., Stroenie grupp i algebr Li, Itogi nauki i tekhniki. Sovremennye problemy matematiki. Fundamentalnye napravleniya, 41, VINITI, M., 1990

[5] Nikitenko E. V., “O nestandartnykh einshteinovykh rasshireniyakh pyatimernykh metricheskikh nilpotentnykh algebr Li”, Sibirskie elektronnye matematicheskie izvestiya, 3 (2006), 115–136 | MR | Zbl

[6] Nikitenko E. V., Nikonorov Yu. G., “Shestimernye einshteinovy solvmnogoobraziya”, Mat. trudy, 8:1 (2005), 71–121 | MR

[7] Nikonorov Yu. G., Rodionov E. D., Slavskii V. V., “Geometriya odnorodnykh rimanovykh mnogoobrazii”, Sovremennaya matematika i ee prilozheniya. Geometriya, 37, 2006, 1–78

[8] Dotti Miatello I., “Ricci curvature of left-invariant metrics on solvable unimodular Lie groups”, Math. Z., 180:2 (1982), 257–263 | MR | Zbl

[9] Gordon C. S. and Kerr M. M., “New homogeneous Einstein metrics of negative Ricci curvature”, Ann. Global Anal. Geom., 19:1 (2001), 75–101 | DOI | MR | Zbl

[10] Heber J., “Noncompact homogeneous Einstein spaces”, Invent. Math., 133:2 (1998), 279–352 | DOI | MR | Zbl

[11] Heintze E., “On homogeneous manifolds of negative curvature”, Math. Ann., 211 (1974), 23–34 | DOI | MR | Zbl

[12] Jacobson N., Lie Algebras, Interscience Tracts in Pure and Applied Mathematics, Interscience Publishers, New York, 1962 | MR | Zbl

[13] Lauret J., “Ricci soliton homogeneous nilmanifolds”, Math. Ann., 319:4 (2001), 715–733 | DOI | MR | Zbl

[14] Lauret J., “Standart Einstein solvmanifolds as critical points”, Quart. J. Math., 52:4 (2001), 463–470 | DOI | MR | Zbl

[15] Lauret J., “Finding Einstein solvmanifolds by a variational method”, Math. Z., 241:1 (2002), 83–99 | DOI | MR | Zbl

[16] Lauret J., A Canonical Compatible Metric for Geometric Structure on Nilmanifolds, Preprint , 2003 arXiv: math.DG/0410579 | MR

[17] Lauret J., Einstein Solvmanifolds Are Standard, Preprint , 2007 arXiv: math.DG/0703472

[18] Lauret J. and Will C., Einstein Solvmanifolds: Existence and Non-Existence Questions, Preprint , 2006 arXiv: math.DG/0602502

[19] Marian A., “On the real moment map”, Math. Res. Lett., 8:5–6 (2001), 779–788 | MR | Zbl

[20] Milnor J., “Curvature of left-invariant metrics on Lie groups”, Adv. Math., 21:3 (1976), 293–329 | DOI | MR | Zbl

[21] Nikolayevsky Y., Einstein Solvable Lie Algebras with a Free Nilradical, Preprint , 2006 arXiv: math.DG/0610020

[22] Nikolayevsky Y., Nilradicals of Einstein Solvmanifolds, Preprint , 2006 arXiv: math.DG/0612117

[23] Nikonorov Yu. G., “Noncompact homogeneous Einstein 5-manifolds”, Geom. Dedicata, 113 (2005), 107–143 | DOI | MR | Zbl

[24] Payne T., The Existence of Soliton Metrics for Nilpotent Lie Groups, Preprint, 2005

[25] Tamaru H., “A class of noncompact homogeneous Einstein manifolds”, Differential Geom. Appl., Proc. Conf. Prague (September 2004), Matfyzpress, Prague, 2005, 119–127 | MR | Zbl

[26] Togo S., “On the derivation of Lie algebras”, Canad. J. Math., 13 (1961), 210–216 | MR

[27] Wang M., “Einstein metrics from symmetry and bundle constructions”, Surveys in Differential Geometry YI: Essays on Einstein Manifolds, Lectures on Geometry and Topology, sponsored by Lehigh University's Journal of Differential Geometry, V. 6, International Press, Cambridge, 1999, 287–325 | MR | Zbl

[28] Will C., “Rank-one Einstein solvmanifolds of dimension 7”, Differential Geom. Appl., 19:3 (2003), 307–318 | DOI | MR | Zbl