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SASAKIAN TWISTOR SPINORS AND THE FIRST DIRAC EIGENVALUE

  • Kim, Eui Chul (Department of Mathematics College of Education Andong National University)
  • Received : 2015.08.29
  • Published : 2016.11.01

Abstract

On a closed eta-Einstein Sasakian spin manifold of dimension $2m+1{\geq}5$, $m{\equiv}0$ mod 2, we prove a new eigenvalue estimate for the Dirac operator. In dimension 5, the estimate is valid without the eta-Einstein condition. Moreover, we show that the limiting case of the estimate is attained if and only if there exists such a pair (${\varphi}_{{\frac{m}{2}}-1}$, ${\varphi}_{\frac{m}{2}}$) of spinor fields (called Sasakian duo, see Definition 2.1) that solves a special system of two differential equations.

Keywords

Acknowledgement

Supported by : Andong National University

References

  1. I. Agricola, The Srni lectures on non-integrable geometries with torsion, Arch. Math. (Brno) 42 (2006), 5-84.
  2. I. Agricola, J. Becker-Bender, and H. Kim, Twistorial eigenvalue estimates for generalized Dirac operators with torsion, Adv. Math. 243 (2013), 296-329. https://doi.org/10.1016/j.aim.2013.05.001
  3. I. Agricola, Th. Friedrich, and M. Kassuba, Eigenvalue estimates for Dirac operators with parallel characteristic torsion, Differential Geom. Appl. 26 (2008), no. 6, 613-624. https://doi.org/10.1016/j.difgeo.2008.04.010
  4. C. Bar, Real Killing spinors and holonomy, Comm. Math. Phys. 154 (1993), no. 3, 509-521. https://doi.org/10.1007/BF02102106
  5. H. Baum, Th. Friedrich, R. Grunewald, and I. Kath, Twistors and Killing Spinors on Riemannian Manifolds, Teubner, Leipzig/Stuttgart, 1991.
  6. Th. Friedrich, Der erste Eigenwert des Dirac-Operators einer kompakten Riemannschen Mannigfaltigkeit nichtnegativer Skalarkrummung, Math. Nachr. 97 (1980), 117-146. https://doi.org/10.1002/mana.19800970111
  7. Th. Friedrich, Dirac operators in Riemannian geometry, Graduatie Studies in Mathematics, Vol. 25, AMS, 2000.
  8. Th. Friedrich and E. C. Kim, The Einstein-Dirac equation on Riemannian spin manifolds, J. Geom. Phys. 33 (2000), no. 1-2, 128-172. https://doi.org/10.1016/S0393-0440(99)00043-1
  9. Th. Friedrich and E. C. Kim, Some remarks on the Hijazi inequality and generalizations of the Killing equation for spinors, J. Geom. Phys. 37 (2001), no. 1-2, 114.
  10. Th. Friedrich and E. C. Kim, Eigenvalues estimates for the Dirac operator in terms of Codazzi tensors, Bull. Korean Math. Soc. 45 (2008), no. 2, 365-373. https://doi.org/10.4134/BKMS.2008.45.2.365
  11. N. Ginoux, The Dirac spectrum, Lecture Notes in Mathematics, 1976, Springer-Verlag, Berlin/Heidelberg, 2009.
  12. E. C. Kim, Dirac eigenvalues estimates in terms of divergencefree symmetric tensors, Bull. Korean Math. Soc. 46 (2009), no. 5, 949-966. https://doi.org/10.4134/BKMS.2009.46.5.949
  13. E. C. Kim, Eigenvalue estimates for generalized Dirac operators on Sasakian manifolds, Ann. Global Anal. Geom. 45 (2014), no. 1, 67-93. https://doi.org/10.1007/s10455-013-9388-7
  14. K.-D. Kirchberg, The first eigenvalue of the Dirac operator on Kahler manifolds, J. Geom. Phys. 7 (1990), no. 4, 449-468. https://doi.org/10.1016/0393-0440(90)90001-J
  15. K.-D. Kirchberg and U. Semmelmann, Complex contact structures and the first eigenvalue of the Dirac operator on Kahler manifolds, Geom. Funct. Anal. 5 (1995), no. 3, 604-618. https://doi.org/10.1007/BF01895834
  16. W. Kramer, U. Semmelmann, and G. Weingart, Quaternionic Killing spinors, Ann. Global Anal. Geom. 16 (1998), no. 1, 63-87. https://doi.org/10.1023/A:1006545828324
  17. W. Kramer, U. Semmelmann, and G. Weingart, Eigenvalue estimates for the Dirac operator on quaternionic Kahler manifolds, Math. Z. 230 (1999), no. 4, 727-751. https://doi.org/10.1007/PL00004715
  18. A. Moroianu, Kahler manifolds with small eigenvalues of the Dirac operator and a conjecture of Lichnerowicz, Ann. Inst. Fourier 49 (1999), no. 5, 1637-1659. https://doi.org/10.5802/aif.1732
  19. Y. Shibuya, The spectrum of Sasakian manifolds, Kodai Math. J. 3 (1980), no. 2, 197-211. https://doi.org/10.2996/kmj/1138036192
  20. S. Tanno, The topology of contact Riemannian manifolds, Illinois J. Math. 12 (1968), 700-717.
  21. K. Yano and M. Kon, Structure on Manifolds, World Scientific, Singapore, 1984.