Hostname: page-component-586b7cd67f-rdxmf Total loading time: 0 Render date: 2024-11-29T18:23:19.804Z Has data issue: false hasContentIssue false

On the formality and strong Lefschetz property of symplectic manifolds

Published online by Cambridge University Press:  01 September 2008

TAEK GYU HWANG
Affiliation:
Department of Mathematical Sciences, Korea Advanced Institute of Science and Technology, Yusong-gu, Daejon 305-701, Republic of Korea. e-mail: [email protected], [email protected]
JIN HONG KIM
Affiliation:
Department of Mathematical Sciences, Korea Advanced Institute of Science and Technology, Yusong-gu, Daejon 305-701, Republic of Korea. e-mail: [email protected], [email protected]

Abstract

The main aim of this paper is to give some non-trivial results that exhibit the difference and similarity between Kähler and symplectic manifolds. To be precise, it is known that simply connected symplectic manifolds of dimension greater than 8, in general, do not satisfy the formality satisfied by all Kähler manifolds. In this paper we show that such non-formality of simply connected symplectic manifolds occurs even in dimension 8. We do this by some complicated but explicit construction of a simply connected non-formal symplectic manifold of dimension 8. In this construction we essentially use a variation of the construction of a simply connected symplectic manifold by Gompf. As a consequence, we can give infinitely many simply connected non-formal symplectic manifolds of any even dimension no less than 8.

Secondly, we show that every compact symplectic manifold admitting a semi-free Hamiltonian circle action with only isolated fixed points must satisfy the strong Lefschetz property satisfied by all Kähler manifolds. This result shows that the strong Lefschetz property for the symplectic manifold admitting Hamiltonian circle actions is closely related to their fixed point set, as expected.

Type
Research Article
Copyright
Copyright © Cambridge Philosophical Society 2008

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

[1]Ahara, K. and Hattori, A.. Four dimensional symplectic S 1-manifolds admitting moment map. J. Fac. Sci. Univ. Tokyo, Sect. 1A, Math. 38 (1991), 251298.Google Scholar
[2]Audin, M.. Hamiltoniens periodiques sur les varieres symplectiques compactes de dimension 4. Geometrie Symplecticque et Mechanique. Lecture Notes in Math. 1416 (1990).Google Scholar
[3]Babenko, I. and Taimanov, I.. On nonformal simply connected symplectic manifolds. Siberian Math. J. 41 (2000), 204217.CrossRefGoogle Scholar
[4]Bott, R. and Tu, L.. Differential forms in algebraic topology. Grad. Text in Math. 82 (Springer 1982).CrossRefGoogle Scholar
[5]Deligne, P., Griffiths, P., Morgan, J. and Sullivan, D.. Real homotopy theory of Kähler manifolds. Invent. Math. 19 (1975), 245274.CrossRefGoogle Scholar
[6]Fernández, M. and Muñoz, V.. An 8-dimensional non-formal simply connected manifold. Topology Appl. 135 (2004), 111117.CrossRefGoogle Scholar
[7]Fernández, M. and Muñoz, V.. An 8-dimensional non-formal simply connected symplectic manifold. to appear in Ann. Math. (arXiv:math.SG/0506449).Google Scholar
[8]Frankel, T.. Fixed points and torsions on Kähler manifolds. Ann. Math 70 (1959), 18.CrossRefGoogle Scholar
[9]Gompf, R.. A new construction of symplectic manifolds. Ann. Math. 142 (1995), 527597.CrossRefGoogle Scholar
[10]Gompf, R. and Stipsicz, A.. 4-manifolds and Kirby calculus. Grad. Stud. Math. 20 (American Mathematical Society 1999).CrossRefGoogle Scholar
[11]Hattori, A.. Symplectic manifolds with semifree Hamiltonian S 1-actions. Tokyo J. Math. 15 (1992), 281296.CrossRefGoogle Scholar
[12]Ibáñez, R., Rudyak, Y., Tralle, A. and Ugarte, L.. On certain geometric and homotopy properties of closed symplectic manifolds. Topology Appl. 127 (2003), 3345.CrossRefGoogle Scholar
[13]Karshon, Y.. Periodic Hamiltonian flows on four dimensional manifolds. Mem. Amer. Math. Soc. (1999).CrossRefGoogle Scholar
[14]Kirwan, F.. The Cohomology of Quotients in Symplectic and Algebraic Geometry. (Princeton University Press 1984).Google Scholar
[15]Lin, Y.. Examples of non-Kähler Hamiltonian circle manifolds with the strong Lefschetz property. preprint (2004) (ArXiv:math.SG/0408345).Google Scholar
[16]Lupton, G. and Oprea, J.. Symplectic manifolds and formality. J. Pure & Appl. Algebra 91 (1994), 193207.CrossRefGoogle Scholar
[17]McDuff, D.. Examples of symplectic simply-connected manifolds with no Kähler structure. J. Diff. Geom. 20 (1984), 267277.Google Scholar
[18]McDuff, D.. The moment map for the circle actions on symplectic manifolds. J. Geom. Phys. 5 (1988), 149160.CrossRefGoogle Scholar
[19]Miller, T.. On the formality of k − 1 connected compact manifolds of dimension less than or equal to 4k − 2. Illinois J. Math. 23 (1979), 253258.CrossRefGoogle Scholar
[20]Neisendorfer, J. and Miller, T.. Formal and coformal spaces. Illinois J. Math. 22 (1978), 565579.CrossRefGoogle Scholar
[21]Ono, K.. Equivariant projective imbedding theorem for symplectic manifolds. J. Fac. Sci. Univ. Tokyo, Sect. 1A, Math. 35 (1988), 381392.Google Scholar
[22]Rudyak, Y. and Tralle, A.. On Thom spaces, Massey products and non-formal symplectic manifolds. Intern. Math. Res. Notices 10 (2000), 495513.CrossRefGoogle Scholar
[23]Tralle, A. and Oprea, J.. Symplectic manifolds with no Kähler structure. Lect. Notes in Math. 1661 (Springer 1997).CrossRefGoogle Scholar
[24]Tolman, S. and Weitsman, J.. On semifree symplectic circle actions with isolated fixed points. Topology 39 (2000), 299309.CrossRefGoogle Scholar