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研究生: 胡喬晏
Joanne Hu
論文名稱: Effective Hamiltonian Circle Actions with Finite Fixed Points on the Complex Projective Plane
指導教授: 姚美琳
Mei-Lin Yau
口試委員:
學位類別: 碩士
Master
系所名稱: 理學院 - 數學系
Department of Mathematics
論文出版年: 2023
畢業學年度: 111
語文別: 英文
論文頁數: 52
中文關鍵詞: Symplectic geometryHamiltonian actionEffective Hamiltonian action
外文關鍵詞: Symplectic geometry, Hamiltonian action, Effective Hamiltonian action
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  • 我們根據 Y. Karshon 博士在1998年發表的論文《 Periodic Hamiltonian Flows on Four Dimensional Manifolds 》研究對於在複射影平面上具有有限不動點的一維球作用進行分類。我們的結論是:每個這樣的作用都會辛同構到線性作用。


    We classify the effective Hamiltonian $S^1$-actions with finite fixed points on the complex projective plane based on the work of Y. Karshon, ``Periodic Hamiltonian Flows on Four Dimensional Manifolds". Our conclusion is that every such action is symplectomorphic to a standard linear case.

    中文摘要 i Abstract ii Acknowledgements iii Contents iv List of Figures v List of Tables v List of Figures v List of Tables vi Chapter 1: Introduction 1 Chapter 2: Backgrounds 3 2.1 Symplectic vector spaces 3 2.2 Symplectic manifolds 4 2.3 Lie group and group action 5 2.3.1 One-parameter groups of diffeomorphisms 5 2.3.2 Lie groups 6 2.4 Hamiltonian Vector Fields and Hamiltonian actions 9 2.5 Compatible almost complex structures 11 2.5.1 Complex structures on vector spaces 11 2.5.2 Compatible structures 12 2.6 The index of a vector field, Morse index and the Euler number 13 2.6.1 The index of a vector field 13 2.6.2 Morse theory 14 2.6.3 The Euler Number 15 2.7 Gradient flows and stable/unstable submanifolds 15 Chapter 3: Hamiltonian S1-actions on (CP2, ω = ωF S ) 18 3.1 The relation between the S1-action and the moment map h 18 3.2 The moment map and Hamiltonian vector field around a fixed point 18 3.3 The existence of gradient spheres 21 Chapter 4: Linear Hamiltonian S1-actions on CP2 22 4.1 The types of the linear actions 22 4.1.1 Case I: gcd(p, q) = 1 22 4.1.2 Case II: gcd(p, q) = k 6 = 1, say p = ̃pk, q = ̃qk, and gcd( ̃p, ̃q) = 1 23 4.2 The graph of a linear action 23 4.2.1 Case (i) p > q > 0 25 4.2.2 Case (ii) p > 0 > q 25 4.2.3 Case (iii) q > p > 0 26 4.2.4 Case (iv) q > 0 > p 27 4.2.5 Case (v) 0 > p > q 28 4.2.6 Case (vi) 0 > q > p 29 Chapter 5: General Hamiltonian S1 action on CP2 30 5.1 The fixed points of an action under our assumptions 30 5.1.1 The minimum occurs at the point guarantees z1 6 = 0 30 5.1.2 The minimum occurs at the point guarantees z2 6 = 0 31 5.1.3 The minimum occurs at the point guarantees z3 6 = 0 31 5.2 The six cases of such action 32 5.2.1 Case 1: At minimum z3 6 = 0 and at maximum z1 6 = 0 32 5.2.2 Case 2: At minimum z2 6 = 0 and at maximum z1 6 = 0 33 5.2.3 Case 3: At minimum z3 6 = 0 and at maximum z2 6 = 0 34 5.2.4 Case 4: At minimum z1 6 = 0 and at maximum z2 6 = 0 35 5.2.5 Case 5: At minimum z2 6 = 0 and at maximum z3 6 = 0 36 5.2.6 Case 6: At minimum z1 6 = 0 and at maximum z3 6 = 0 37 Conclusion 39 References 41 List of Figures 1 Case (i) p > q > 0 25 2 Case (ii) p > 0 > q 26 3 Case (iii) q > p > 0 27 4 Case (iv) q > 0 > p 28 5 Case (v) 0 > p > q 28 6 Case (vi) 0 > q > p 29 7 Case 1: At minimum z3 6 = 0 and at maximum z1 6 = 0 33 8 Case 2: At minimum z2 6 = 0 and at maximum z1 6 = 0 34 9 Case 3: At minimum z3 6 = 0 and at maximum z2 6 = 0 35 10 Case 4: At minimum z1 6 = 0 and at maximum z2 6 = 0 36 11 Case 5: At minimum z2 6 = 0 and at maximum z3 6 = 0 37 12 Case 6: At minimum z1 6 = 0 and at maximum z3 6 = 0 38 13 The graph of an effective Hamiltonian circle action on the complex projective plane 39 List of Tables 1 Table of linear action graphs 40

    [1] K. Ahara and A. Hattori. 4-dimensional symplectic S1-manifolds admitting moment map. J. Fac.
    Sci. Univ. Tokyo Sect. IA Math., 38(2):251–298, 1991.

    [2] M. Audin. Torus actions on symplectic manifolds, volume 93 of Progress in Mathematics.
    Birkhäuser Verlag, Basel, revised edition, 2004.

    [3] A. Baker. Matrix groups. Springer Undergraduate Mathematics Series. Springer-Verlag London,
    Ltd., London, 2002. An introduction to Lie group theory.

    [4] D. Barden and C. Thomas. An introduction to differential manifolds. Imperial College Press,
    London, 2003.

    [5] A. Cannas da Silva. Lectures on symplectic geometry, volume 1764 of Lecture Notes in Mathe-
    matics. Springer-Verlag, Berlin, 2001.

    [6] A. Cannas da Silva. Symplectic toric manifolds. In Symplectic geometry of integrable Hamiltonian
    systems (Barcelona, 2001), Adv. Courses Math. CRM Barcelona, pages 85–173. Birkhäuser, Basel,
    2003.

    [7] R. Chiang and L. Kessler. Cyclic actions on rational ruled symplectic four-manifolds. Transform.
    Groups, 24(4):987–1000, 2019.

    [8] M. D. Crossley. Essential topology. Springer Undergraduate Mathematics Series. Springer-Verlag
    London, Ltd., London, 2005.

    [9] R. Fintushel. Circle actions on simply connected 4-manifolds. Trans. Amer. Math. Soc., 230:147–
    171, 1977.

    [10] R. Fintushel. Classification of circle actions on 4-manifolds. Trans. Amer. Math. Soc., 242:377–390,
    1978.

    [11] L. Godinho. On certain symplectic circle actions. J. Symplectic Geom., 3(3):357–383, 2005.

    [12] A. Hatcher. Algebraic topology. Cambridge University Press, Cambridge, 2002.

    [13] D. Jang. Symplectic periodic flows with exactly three equilibrium points. Ergodic Theory Dynam.
    Systems, 34(6):1930–1963, 2014.

    [14] D. Jang. Circle actions on almost complex manifolds with isolated fixed points. J. Geom. Phys.,
    119:187–192, 2017.

    [15] D. Jang. Symplectic circle actions with isolated fixed points. J. Symplectic Geom., 15(4):1071–
    1087, 2017.
    41

    [16] D. Jang. Circle actions on oriented manifolds with discrete fixed point sets and classification in
    dimension 4. J. Geom. Phys., 133:181–194, 2018.

    [17] Y. Karshon. Periodic Hamiltonian flows on four-dimensional manifolds. Mem. Amer. Math. Soc.,
    141(672):viii+71, 1999.

    [18] Y. Karshon and L. Kessler. Circle and torus actions on equal symplectic blow-ups of CP2. Math.
    Res. Lett., 14(5):807–823, 2007.

    [19] S. Lang. Algebra, volume 211 of Graduate Texts in Mathematics. Springer-Verlag, New York,
    third edition, 2002.

    [20] H. Li and S. Tolman. Hamiltonian circle actions with minimal fixed sets. Internat. J. Math.,
    23(8):1250071, 36, 2012.

    [21] P. Li. Circle action with prescribed number of fixed points. Acta Math. Sin. (Engl. Ser.),
    31(6):1035–1042, 2015.

    [22] N. Lindsay. Hamiltonian circle actions on complete intersections. Bull. Lond. Math. Soc.,
    54(1):206–212, 2022.

    [23] D. McDuff. Blow ups and symplectic embeddings in dimension 4. Topology, 30(3):409–421, 1991.

    [24] D. McDuff and D. Salamon. Introduction to symplectic topology. Oxford Mathematical Mono-
    graphs. The Clarendon Press, Oxford University Press, New York, second edition, 1998.

    [25] J. Milnor. Morse theory. Princeton University Press, Princeton, N.J.„ 1963. Based on lecture
    notes by M. Spivak and R. Wells.

    [26] J. R. Munkres. Topology: a first course. Prentice-Hall, Inc., Englewood Cliffs, N.J.„, 1975.

    [27] J. R. Munkres. Elements of algebraic topology. Addison-Wesley Publishing Company, Menlo Park,
    CA, 1984.

    [28] L. W. Tu. An introduction to manifolds. Universitext. Springer,

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