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Non-degenerate para-complex structures in 6D with large symmetry groups

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Abstract

For an almost product structure J on a manifold M of dimension 6 with non-degenerate Nijenhuis tensor \(N_J\), we show that the automorphism group \(G=\mathrm{Aut}(M,J)\) has dimension at most 14. In the case of equality G is the exceptional Lie group \(G_2^*\). The next possible symmetry dimension is proved to be equal to 10, and G has Lie algebra \(\mathfrak {sp}(4,{\mathbb R})\). Both maximal and submaximal symmetric structures are globally homogeneous and strictly nearly para-Kähler. We also demonstrate that whenever the symmetry dimension is at least 9, then the automorphism algebra acts locally transitively.

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Notes

  1. If \(o\in M\) belongs to a singular orbit, this fact is usually false.

References

  1. Alekseevsky, D.: Pseudo-Kähler and para-Kähler symmetric spaces. In: Cortés, V. (ed.) Handbook of Pseudo-Riemannian Geometry and Supersymmetry. IRMA Lectures in Mathematics and Theoretical Physics. EMS, Zurich (2010)

    Google Scholar 

  2. Alekseevsky, D.V., Kruglikov, B.S., Winther, H.: Homogeneous almost complex structures in dimension 6 with semi-simple isotropy. Ann. Glob. Anal. Geom. 46, 361–387 (2014)

    Article  MathSciNet  MATH  Google Scholar 

  3. Alekseevsky, D.V., Medori, C., Tomassini, A.: Homogeneous para-Kähler Einstein manifolds. Russ. Math. Surv. 64(1), 1–4 (2009)

    Article  MATH  Google Scholar 

  4. Bryant, R.L.: Conformal geometry and 3-plane fields on 6-manifolds. Developments of Cartan geometry and related mathematical problems. In: RIMS Symposium Proceedings, Kyoto University, vol. 150, No. 2, pp. 1–15 (2006)

  5. Butruille, J.-B.: Classification des variétés approximativement kähleriennes homogènes. Ann. Glob. Anal. Geom. 27(3), 201–225 (2005)

    Article  MathSciNet  MATH  Google Scholar 

  6. Cruceanu, V., Fortuny, P., Gadea, P.M.: A survey on paracomplex geometry. Rocky Mt. J. Math. 26, 83–115 (1996)

    Article  MathSciNet  MATH  Google Scholar 

  7. Guichardet, A.: Cohomologie des Groupes Topologiques et des Algèbres de Lie. Cedic/Nathan, Paris (1980)

    MATH  Google Scholar 

  8. Gray, A.: Nearly Kähler manifolds. J. Differ. Geom. 4, 283–309 (1970)

    Article  MATH  Google Scholar 

  9. Gutowski, J.B., Sabra, W.A.: Para-complex geometry and gravitational instantons. Class. Quantum Gravity 30, 195001 (2013)

    Article  MathSciNet  MATH  Google Scholar 

  10. Hou, Z., Deng, S., Kaneyuki, S., Nishiyama, K.: Dipolarizations in semisimple Lie algebras and homogeneous para-Kähler manifolds. J. Lie Theory 9(1), 215–232 (1999)

    MathSciNet  MATH  Google Scholar 

  11. Ivanov, S., Zamkovoy, S.: ParaHermitian and paraquaternionic manifolds. Differ. Geom. Appl. 23(2), 205–234 (2005)

    Article  MathSciNet  MATH  Google Scholar 

  12. Kath, I.: \(G^*_{2(2)}\)-structures on pseudo-Riemannian manifolds. J. Geom. Phys. 27(3–4), 155–177 (1998)

    Article  MathSciNet  MATH  Google Scholar 

  13. Kruglikov, B.: Non-existence of higher-dimensional pseudoholomorphic submanifolds. Manuscr. Math. 111, 51–69 (2003)

    Article  MathSciNet  MATH  Google Scholar 

  14. Kruglikov, B.: Symmetries of almost complex structures and pseudoholomorphic foliations. Intern. J. Math. 25(8), 1450079 (2014)

    Article  MathSciNet  MATH  Google Scholar 

  15. Kruglikov, B., Lychagin, V.: Geometry of differential equations. In: Krupka, D., Saunders, D. (eds.) Handbook of Global Analysis, pp. 725–772. Elsevier, Amsterdam (2008)

    Chapter  Google Scholar 

  16. Kruglikov, B.: The gap phenomenon in parabolic geometry. J. Reine Angew. Math. (Crelle’s J.). arXiv:1303.1307. doi:10.1515/crelle-2014-0072 (2014)

  17. Kruglikov, B., Winther, H.: Almost complex structures in 6D with non-degenerate Nijenhuis tensors and large symmetry groups. Ann. Glob. Anal. Geom. 50, 297–314 (2016)

    Article  MathSciNet  MATH  Google Scholar 

  18. Kruglikov, B., Winther, H.: Reconstruction from Representations: Jacobi via Cohomology. arXiv:1611.05334; to appear in Journal of Lie Theory (2017)

  19. Libermann, P.: Sur les structures presque paracomplexes. C. R. Acad. Sci. Paris 234, 2517–2519 (1952)

    MathSciNet  MATH  Google Scholar 

  20. Mostow, G.D.: On maximal subgroups of real Lie groups. Ann. Math. 74, 503–517 (1961)

    Article  MathSciNet  MATH  Google Scholar 

  21. Rashevskii, P.K.: The scalar fields in a stratified space. Trudy Sem. Vektor. Tenzor. Analizu (Russian) 6, 225–248 (1948)

    MathSciNet  Google Scholar 

  22. Schäfer, L.: Para-\(tt^*\)-bundles on the tangent bundle of an almost para-complex manifold. Ann. Global Anal. Geom. 32(2), 125–145 (2007)

    Article  MathSciNet  MATH  Google Scholar 

  23. Spencer, D.C.: Overdetermined systems of linear partial differential equations. Bull. Am. Math. Soc. 75, 179–239 (1969)

    Article  MathSciNet  MATH  Google Scholar 

  24. Thurston, W.P.: A generalization of the Reeb stability theorem. Topology. 13, 347–352 (1974)

    Article  MathSciNet  MATH  Google Scholar 

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Acknowledgements

Both authors were partially supported by the Norwegian Research Council and DAAD project of Germany.

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Kruglikov, B.S., Winther, H. Non-degenerate para-complex structures in 6D with large symmetry groups. Ann Glob Anal Geom 52, 341–362 (2017). https://doi.org/10.1007/s10455-017-9561-5

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