Computing Homology Invariants of Legendrian Knots

  title={Computing Homology Invariants of Legendrian Knots},
  author={Emily E. Casey and M. Henry},
  journal={arXiv: Symplectic Geometry},
The Chekanov-Eliashberg differential graded algebra of a Legendrian knot L is a rich source of Legendrian knot invariants, as is the theory of generating families. The set P(L) of homology groups of augmentations of the Chekanov-Eliashberg algebra is an invariant, as is a count of objects from the theory of generating families called graded normal rulings. This article gives two results demonstrating the usefulness of computing the homology group of an augmentation using a combinatorial… 
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