SUNY at Stony Brook MAT 667:
Spring 2012

Topics covered

  • Goldman bracket, definition and Jacobi identity (the Stone Alge4bra or a pair of pairs of points occuring twice), examples.
  • One to one correspondance between free homotopy classes of oriented closed curves on a space X and conjugacy classes the fundamamental group of X.
  • The number of terms of the Goldman bracket of two classes is a lower bound of their intersection number.
  • "Following" intersection and self-intersection point of curves on a surface along a homotopy.
  • Homework: The Goldman Lie algebra of curves in the torus.
  • Equivariant homology of the free loop space of a free manifold (in degree 0 and 1) (equivariant with respect to the circle action rotating the domain)
  • Homework: Let a and b denote the based homotopy classes corresponding to the boundary components of the pair of pant, oriented so that aB has self-intersection one. Consider the fundamental group of the pairs of pants with generators a, b. Compute the brackets, [aB, Ab] [aab, aB], [AAB, aB].
  • The String Topology Lie algebra in the equivariant homology of the free loop space of a manifold (We will work out first on 3-manifolds and degree 0 and 1 equivariant homology).
  • Classification of three manifolds.
  • The String topology Lie algebra on a product of a surface with a circle. The String topology Lie algebra on Seifert fibered spaces.
  • Several examples of 1-cycles in the equivariant homology of the free loop space of a free manifold.
  • Brackets on the zeroeth and first equivariant homology groups of the free loop space of three manifolds.

Tentative List of Topics and References

Below is a preliminary list of topics, not necessarily in the order they will be discussed.

  • The Lie bialgebra of curves on surfaces
    • Definition and examples. Goldman.
    • The Goldman Lie algebra of curves in the torus.
    • The Goldman Lie algebra of curves in a surface with boundary. Chas
    • Relationship between the Goldman Lie algebra and formal symplectic geometry. Kawazumi- Kuno
    • Digression: Self-intersections are Gaussian. Chas-Lalley
    • The Goldman Lie algebra characterizes homeomorphisms. Gadgil,
    • Intersection of and self-intersection number of curves and relation to the Goldman Lie algebra. Chas, Chas-Krongold
    • The Lie bialgebra of curves on surfaces. Turaev
    • Turaev's coalgebra and self-intersection of curves. Chas-Krongold, Le Donne.
    • The center of the Goldman Lie algebra Etingoff,
  • Goldman Lie algebra for Fuchsian groups
    • Definition and examples.
    • The Goldman Lie algebra on the Modular Surface.
    • Intersection of geodesics on the Modular surface.
  • String topology Chas-Sullivan
  • Andersen-Mattes-Reshetikhin algebra of chord diagrams Ellegaard Andersen, Mattes, Reshetikhin and Cahn's generalization's of Turaev's cobracket Cahn