Skip to main content
Log in

Einstein metrics, harmonic forms, and symplectic four-manifolds

  • Published:
Annals of Global Analysis and Geometry Aims and scope Submit manuscript

Abstract

If \(M\) is the underlying smooth oriented four-manifold of a Del Pezzo surface, we consider the set of Riemannian metrics \(h\) on \(M\) such that \(W^+(\omega , \omega )> 0\), where \(W^+\) is the self-dual Weyl curvature of \(h\), and \(\omega \) is a non-trivial self-dual harmonic two-form on \((M,h)\). While this open region in the space of Riemannian metrics contains all the known Einstein metrics on \(M\), we show that it contains no others. Consequently, it contributes exactly one connected component to the moduli space of Einstein metrics on \(M\).

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. Anderson, M.T.: The \(L^2\) structure of moduli spaces of Einstein metrics on 4-manifolds. Geom. Funct. Anal. 2, 29–89 (1992)

    Article  MATH  MathSciNet  Google Scholar 

  2. Apostolov, V., Tønnesen-Friedman, C.: A remark on Kähler metrics of constant scalar curvature on ruled complex surfaces. Bull. Lond. Math. Soc. 38, 494–500 (2006)

    Article  MATH  Google Scholar 

  3. Arezzo, C., Pacard, F.: Blowing up and desingularizing constant scalar curvature Kähler manifolds. Acta Math. 196, 179–228 (2006)

    Article  MATH  MathSciNet  Google Scholar 

  4. Besse, A.L.: Einstein Manifolds, Ergebnisse der Mathematik und ihrer Grenzgebiete (3), vol. 10. Springer, Berlin (1987)

    Google Scholar 

  5. Besson, G., Courtois, G., Gallot, S.: Entropies et rigidités des espaces localement symétriques de courbure strictement négative. Geom. Funct. Anal. 5, 731–799 (1995)

    Article  MATH  MathSciNet  Google Scholar 

  6. Blair, D.E., Draghici, T.: Remarks on Weyl curvature in almost Kähler geometry. Bull. Math. Soc. Sci. Math. Roum. (N.S.) 52(100), 241–249 (2009)

    MathSciNet  Google Scholar 

  7. Böhm, C.: Inhomogeneous Einstein metrics on low-dimensional spheres and other low-dimensional spaces. Invent. Math. 134, 145–176 (1998)

    Article  MATH  MathSciNet  Google Scholar 

  8. Boyer, C.P., Galicki, K., Kollár, J.: Einstein metrics on spheres. Ann. Math. (2) 162, 557–580 (2005)

    Article  MATH  Google Scholar 

  9. Burns, D., De Bartolomeis, P.: Stability of vector bundles and extremal metrics. Invent. Math. 92, 403–407 (1988)

    Article  MATH  MathSciNet  Google Scholar 

  10. Chen, X.X., LeBrun, C., Weber, B.: On conformally Kähler, Einstein manifolds. J. Am. Math. Soc. 21, 1137–1168 (2008)

    Article  MATH  MathSciNet  Google Scholar 

  11. Demazure, M.: Surfaces de del Pezzo, II, III, IV, V, in Séminaire sur les Singularités des Surfaces, Lecture Notes in Mathematics, vol. 777, pp. 21–69. Springer, Berlin (1980)

  12. Derdziński, A.: Self-dual Kähler manifolds and Einstein manifolds of dimension four. Compos. Math. 49, 405–433 (1983)

    MATH  Google Scholar 

  13. DeTurck, D.M., Kazdan, J.L.: Some regularity theorems in Riemannian geometry. Ann. Sci. École Norm. Sup. (4) 14, 249–260 (1981)

    MATH  MathSciNet  Google Scholar 

  14. Donaldson, S.K.: Scalar curvature and stability of toric varieties. J. Differ. Geom. 62, 289–349 (2002)

    MATH  MathSciNet  Google Scholar 

  15. Gursky, M.J.: Four-manifolds with \(\delta {W}^+=0\) and Einstein constants of the sphere. Math. Ann. 318, 417–431 (2000)

    Article  MATH  MathSciNet  Google Scholar 

  16. Kim, I.: Almost-Kähler anti-self-dual metrics. Ph.D. thesis, State University of New York, Stony Brook (2014)

  17. Kim, J., LeBrun, C., Pontecorvo, M.: Scalar-flat Kähler surfaces of all genera. J. Reine Angew. Math. 486, 69–95 (1997)

    MATH  MathSciNet  Google Scholar 

  18. Kirchberg, K.-D.: Some integrability conditions for almost Kähler manifolds. J. Geom. Phys. 49, 101–115 (2004)

    Article  MATH  MathSciNet  Google Scholar 

  19. LeBrun, C.: Scalar-flat Kähler metrics on blown-up ruled surfaces. J. Reine Angew. Math. 420, 161–177 (1991)

    MATH  MathSciNet  Google Scholar 

  20. LeBrun, C.: Einstein metrics and Mostow rigidity. Math. Res. Lett. 2, 1–8 (1995)

    Article  MATH  MathSciNet  Google Scholar 

  21. LeBrun, C.: Polarized 4-manifolds, extremal Kähler metrics, and Seiberg–Witten theory. Math. Res. Lett. 2, 653–662 (1995)

    Article  MATH  MathSciNet  Google Scholar 

  22. LeBrun, C.: Yamabe constants and the perturbed Seiberg–Witten equations. Commun. Anal. Geom. 5, 535–553 (1997)

    MATH  MathSciNet  Google Scholar 

  23. LeBrun, C.: On Einstein, Hermitian 4-manifolds. J. Differ. Geom. 90, 277–302 (2012)

    MATH  MathSciNet  Google Scholar 

  24. Manin, Y.I.: Cubic Forms: Algebra, Geometry, Arithmetic. North-Holland Publishing Co., Amsterdam (1974). (Translated from the Russian by M. Hazewinkel)

    MATH  Google Scholar 

  25. Narasimhan, M.S., Seshadri, C.S.: Stable and unitary vector bundles on a compact Riemann surface. Ann. Math. (2) 82, 540–567 (1965)

    Article  MATH  MathSciNet  Google Scholar 

  26. Odaka, Y., Spotti, C., Sun, S.: Compact moduli spaces of Del Pezzo surfaces and Kähler–Einstein metrics. e-print (2012). arXiv:1210.0858 [math.DG] (to appear in J. Differ. Geom.)

  27. Page, D.: A compact rotating gravitational instanton. Phys. Lett. 79B, 235–238 (1979)

    MathSciNet  Google Scholar 

  28. Penrose, R., Rindler, W.: Spinors and Space-Time. Spinor and Twistor Methods in Space-Time Geometry, vol. 2. Cambridge University Press, Cambridge (1986)

    Google Scholar 

  29. Rollin, Y., Singer, M.: Construction of Kähler surfaces with constant scalar curvature. J. Eur. Math. Soc. (JEMS) 11, 979–997 (2009)

    Article  MATH  MathSciNet  Google Scholar 

  30. Sekigawa, K.: On some 4-dimensional compact Einstein almost Kähler manifolds. Math. Ann. 271, 333–337 (1985)

    Article  MATH  MathSciNet  Google Scholar 

  31. Shu, Y.: Compact complex surfaces and constant scalar curvature Kähler metrics. Geom. Dedicata 138, 151–172 (2009)

    Article  MATH  MathSciNet  Google Scholar 

  32. Tian, G.: On Calabi’s conjecture for complex surfaces with positive first Chern class. Invent. Math. 101, 101–172 (1990)

    Article  MATH  MathSciNet  Google Scholar 

  33. Trudinger, N.: Remarks concerning the conformal deformation of metrics to constant scalar curvature. Ann. Scuola Norm. Sup. Pisa 22, 265–274 (1968)

    MATH  MathSciNet  Google Scholar 

  34. van Coevering, C.: Sasaki-Einstein 5-manifolds associated to toric 3-Sasaki manifolds. N. Y. J. Math. 18, 555–608 (2012)

    MATH  Google Scholar 

  35. Yau, S.T.: On the curvature of compact Hermitian manifolds. Invent. Math. 25, 213–239 (1974)

    Article  MATH  MathSciNet  Google Scholar 

Download references

Acknowledgments

The author would like to thank Tedi Draghici for subsequently pointing out some of his own related work, and the anonymous referee for suggesting ways to streamline and clarify the exposition. This work was supported in part by NSF Grant DMS-1205953.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Claude LeBrun.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

LeBrun, C. Einstein metrics, harmonic forms, and symplectic four-manifolds. Ann Glob Anal Geom 48, 75–85 (2015). https://doi.org/10.1007/s10455-015-9458-0

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s10455-015-9458-0

Keywords

Mathematics Subject Classification

Navigation