manuscripta mathematica

, Volume 75, Issue 1, pp 49–63 | Cite as

The equator map and the negative exponential functional

  • Min-Chun Hong
Article
  • 25 Downloads

Abstract

We define a negative exponential harmonic map from the ballB n of ℝn into the sphereS n of ℝ n+1 . We prove that the equator map\(u^* = (\frac{x}{{\left| x \right|}},0)\) is a negative exponential harmonic map, but not stable for the negative exponential functional whenn≥2. Moreover, we consider maps from a ballB n into the unit sphereS m of ℝm+1 wherem≥2, and prove that no nonconstant, non surjective map can reach either the minimum or the maximum of the negative exponential functional.

Keywords

Weak Solution Riemannian Manifold Unit Ball Energy Density Nonlinear Elliptic System 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. [AL]
    F. J. Almgren and E. Lieb,Singularities of energy-minimizer maps from the ball to the sphere, Bull. Amer. Math. Soc.17 (1987), 304–306MATHMathSciNetCrossRefGoogle Scholar
  2. [B]
    H. Brézis,S k -valued maps with singularities, Springer Lecture Notes in Math.1365 (1989), 1–30CrossRefGoogle Scholar
  3. [BCL]
    H. Brézis, J. M. Coron and E. Lieb,Harmonic maps with defects, Bull. London Math. Soc.20 (1988), 385–524MathSciNetGoogle Scholar
  4. [C]
    J. M. Coron,Harmonic maps with values into sphere, Proc. ICM (1990)Google Scholar
  5. [EL]
    J. Eells and L. Lemaire,Another report on Harmonic maps, Bull. London Math. Soc.20 (1988), 385–524MATHMathSciNetGoogle Scholar
  6. [ES]
    J. Eells and J. H. Sampson,Harmonic mappings of Riemannian manifolds, Amer. J. Math.86 (1964), 109–160MATHCrossRefMathSciNetGoogle Scholar
  7. [G]
    M. Giaquinta,Mutiple integrals in the calculus of variations and nonlinear elliptic systems, Princeton Univ. press, 1983Google Scholar
  8. [GG]
    M. Giaquinta and E. Giusti,The singular set of the minima of certain quadratic functionals, Ann. Sc. Norm. Sup. Pisa11 (1984), 45–55MATHMathSciNetGoogle Scholar
  9. [GS]
    M. Giaquinta and J. Souček,Harmonic maps into a hemisphere, Ann. Sc. Norm. Sup. Pisa12 (1985), 81–90MATHGoogle Scholar
  10. [HKL]
    R. Hardt, D. Kinderlehere and F. H. Lin,Existence and partial regularity of static liquid crystal configurations, Comm. Math. Phy.105 (1986), 547–570MATHCrossRefGoogle Scholar
  11. [HL1]
    R. Hardt and F. H. Lin,A remark on H 1 mappings, Manus. Math.56 (1986), 1–10MATHCrossRefMathSciNetGoogle Scholar
  12. [HL2]
    R. Hardt and F. H. Lin,Mappings minimizing the L p norm of the gradient, Comm. Pure Appl. Math.40 (1987), 555–588MATHMathSciNetGoogle Scholar
  13. [H]
    F. Hélein,Minima de la fonctionnelle energye libre de cristaux liquides, C. R. Acad. Sc. Paris305 (1987), 565–568MATHGoogle Scholar
  14. [Hi]
    S. Hildebrandt,Harmonic mappings of Riemannian manifolds, Springer lectures notes in Math.1161 (1985), 1–117MathSciNetGoogle Scholar
  15. [HKW]
    S. Hildebrandt, H. Kaul and K. Widman,An existence theorem for harmonic mappings of Riemannian manifolds, Acta Math.138 (1977), 1–6MATHCrossRefMathSciNetGoogle Scholar
  16. [JK]
    W. Jäger and H. Kaul,Rotationally symmetric harmonic map from a ball into a sphere and the regularity problem for weak solutions of elliptic systems, J. Reine. U. Angew. Math.34 (1983), 146–161Google Scholar
  17. [LL]
    L. D. Landau and E. M. Lifshitz,Statistical Physics, Pergamon Press, New York 1980Google Scholar
  18. [L]
    F. H. Lin, A remark on the map\(\frac{x}{{\left| x \right|}}\), C. R. Acad. Sc. Paris305 (1987) 529–531MATHGoogle Scholar
  19. [SU1]
    R. Schoen and K. Uhlenbeck,A regularity theorem for harmonic maps, J. Diff. Geom.17 (1982), 307–335.MathSciNetMATHGoogle Scholar
  20. [SU2]
    —,Regularity of minimizing harmonic maps into the sphere, Invent. Math.78 (1984), 89–100MATHCrossRefMathSciNetGoogle Scholar
  21. [SU3]
    —,Boundary regularity and the Dirichlet problem for harmonic maps, J. Diff. Geom.18 (1983), 253–268MATHMathSciNetGoogle Scholar

Copyright information

© Springer-Verlag 1992

Authors and Affiliations

  • Min-Chun Hong
    • 1
  1. 1.Mathematics SepartmentZhejiang UniversityHangzhouP. R. China

Personalised recommendations