Skip to main content
Log in

Abstract

Basing ourselves on the categorical notions of central extensions and commutators in the framework of semi-abelian categories relative to a Birkhoff subcategory, we study central extensions of Leibniz algebras with respect to the Birkhoff subcategory of Lie algebras, called \(\mathsf {Lie}\)-central extensions. We obtain a six-term exact homology sequence associated to a \(\mathsf {Lie}\)-central extension. This sequence, together with the relative commutators, allows us to characterize several classes of \(\mathsf {Lie}\)-central extensions, such as \(\mathsf {Lie}\)-trivial extensions, \(\mathsf {Lie}\)-stem extensions and \(\mathsf {Lie}\)-stem covers, and to introduce and characterize \(\mathsf {Lie}\)-unicentral, \(\mathsf {Lie}\)-capable, \(\mathsf {Lie}\)-solvable and \(\mathsf {Lie}\)-nilpotent Leibniz algebras.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Similar content being viewed by others

References

  1. Borceux, F.: A survey of semi-abelian categories. In Galois theory, Hopf algebras and semi-abelian categories. Fields Inst. Commun. 43, 27–60 (2004)

    MATH  Google Scholar 

  2. Borceaux, F., Bourn, D.: Mal’cev, protomodular, homological and semi-abelian categories. In: Mathematics and Its Applications, vol. 566. Kluwer, New York (2004)

  3. Bourn, D.: \(3 \times 3\) lemma and protomodularity. J. Algebra 236, 778–795 (2001)

    Article  MathSciNet  MATH  Google Scholar 

  4. Cañete, E.M., Khudoyberdiyev, AKh: The classification of 4-dimensional Leibniz algebras. Linear Algebra Appl. 439(1), 273–288 (2013)

    Article  MathSciNet  MATH  Google Scholar 

  5. Casas, J.M., Insua, M.A., Ladra, M., Ladra, S.: An algorithm for the classification of 3-dimensional complex Leibniz algebras. Linear Algebra Appl. 436, 3747–3756 (2012)

    Article  MathSciNet  MATH  Google Scholar 

  6. Casas, J.M., Khmaladze, E., Ladra, M.: On solvability and nilpotency of Leibniz \(n\)-algebras. Commun. Algebra 34(8), 2769–2780 (2006)

    Article  MathSciNet  MATH  Google Scholar 

  7. Casas, J.M., Khmaladze, E., Ladra, M., Van der Linden, T.: Homology and cenral extensions of Leibniz and Lie \(n\)-algebras. Homol. Homotopy Appl. 13(1), 59–74 (2011)

    Article  MATH  Google Scholar 

  8. Casas, J.M., Van der Linden, T.: A relative theory of universal central extensions. In: Pré-Publicaçoes do Departamento de Matemática, Universidade de Coimbra (preprint number 09) (2009)

  9. Casas, J.M., Van der Linden, T.: Universal central extensions in semi-abelian categories. Appl. Category Struct. 22(1), 253–268 (2014)

    Article  MathSciNet  MATH  Google Scholar 

  10. Cuvier, C.: Algèbres de Leibnitz: définitions, propriétés. Ann. Sci. Écol. Norm. Sup. 27(4), 1–45 (1994)

    MathSciNet  MATH  Google Scholar 

  11. Everaert, T.: Higher central extensions and Hopf formulae. J. Algebra 328(8), 1771–1789 (2010)

    Article  MathSciNet  MATH  Google Scholar 

  12. Everaert, T.: Relative commutator theory in varieties of \(\Omega \)-groups. J. Pure Appl. Algebra 210(1), 1–10 (2007)

    Article  MathSciNet  MATH  Google Scholar 

  13. Everaert, T., Gran, M.: On low-dimensional homology in categories. Homol. Homotopy Appl. 9(1), 275–293 (2007)

    Article  MathSciNet  MATH  Google Scholar 

  14. Everaert, T., Gran, M., Van der Linden, T.: Higher Hopf formulae for homology via Galois theory. Adv. Math. 217(5), 2231–2267 (2008)

    Article  MathSciNet  MATH  Google Scholar 

  15. Everaert, T., Van der Linden, T.: Baer invariants in semi-abelian categories I: general theory. Theory Appl. Category 12(1), 1–33 (2004)

    MathSciNet  MATH  Google Scholar 

  16. Everaert, T., Van der Linden, T.: Baer invariants in semi-abelian categories II: homology. Theory Appl. Category 12(1), 195–224 (2004)

    MathSciNet  MATH  Google Scholar 

  17. Furtado-Coelho, J.: Homology and generalized Bear invariants. J. Algebra 40(2), 596–609 (1976)

    Article  MathSciNet  MATH  Google Scholar 

  18. Gran, M., Van der Linden, T.: On the second cohomology group in semi-abelian categories. J. Pure Appl. Algebra 212, 636–651 (2008)

    Article  MathSciNet  MATH  Google Scholar 

  19. Higgins, P.J.: Groups with multiple operators. Proc. Lond. Math. Soc. (3) 6, 366–416 (1956)

  20. Humphreys, J.E.: Introduction to Lie algebras and representation theory. In: Graduate Text in Mathematics, vol. 9. Springer, New York (1972)

  21. Janelidze, G., Kelly, G.M.: Galois theory and a general notion of central extension. J. Pure Appl. Algebra 97, 135–161 (1994)

    Article  MathSciNet  MATH  Google Scholar 

  22. Janelidze, G., Márki, L., Tholen, W.: Semi-abelian categories. J. Pure Appl. Algebra 168, 367–386 (2002)

    Article  MathSciNet  MATH  Google Scholar 

  23. Kurdiani, R., Pirashvili, T.: A Leibniz algebra structure on the second tensor power. J. Lie Theory 12(2), 583–596 (2002)

    MathSciNet  MATH  Google Scholar 

  24. Loday, J.-L.: Cyclic homology. Grundl. Math. Wiss. Bd. 301 (Springer, Berlin) (1992)

  25. Loday, J.-L.: Une version non commutative des algèbres de Lie: les algèbres de Leibniz. L’Enseign. Math. 39, 269–292 (1993)

    Google Scholar 

  26. Loday, J.-L., Pirashvili, T.: Universal enveloping algebras of Leibniz algebras and (co)homology. Math. Ann. 296, 139–158 (1993)

    Article  MathSciNet  MATH  Google Scholar 

  27. Michael, F.I.: A note on the five lemma. Appl. Category Struct. 21, 441–448 (2013)

    Article  MathSciNet  MATH  Google Scholar 

  28. Omirov, B.A.: Conjugacy of Cartan subalgebras of complex finite-dimensional Leibniz algebras. J. Algebra 302(2), 887–896 (2006)

    Article  MathSciNet  MATH  Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to J. M. Casas.

Additional information

The authors wish to thank Prof. Teimuraz Pirashvili and anonymous referees for their suggestions and help in improving the presentation of this paper. Authors were supported by Ministerio de Economía y Competitividad (Spain) (European FEDER support included), Grant MTM2013-43687-P. E. Khmaladze was supported by Xunta de Galicia, Grant EM2013/016 (European FEDER support included) and by Shota Rustaveli National Science Foundation, Grant FR/189/5-113/14.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Casas, J.M., Khmaladze, E. On \(\mathsf {Lie}\)-central extensions of Leibniz algebras. RACSAM 111, 39–56 (2017). https://doi.org/10.1007/s13398-016-0274-6

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s13398-016-0274-6

Keywords

Mathematics Subject Classification

Navigation