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4:00 pm Monday, November 17, 2008 Topology Seminar: Algebraic structures in contact homologyby John Etnyre (Georgia Institute of Technology) in HB 427- Contact homology is a very powerful invariant of Legendrian knots in R
^{3}, but as it is a non-commutative algebra it can sometimes be difficult to work with. So in applications one usually tries to extract information out of the differential graded algebra (dga) underlying the homology. This technique does not always work but when it does it is very effective. There is a great deal of hidden algebraic structure in the dga that has, so far, been largely ignored. In this talk I will discuss this structure and show how it can be bundled together to give an A^{∞} algebra structure. I will also show that all this structure does actually provide nontrivial invariants of Legendrian knots.Submitted by shelly@rice.edu |